D_SKywalk,

he bajado la versión de svgalib modificada por ti según el manual, las descomprimo y hago un make install, aquí te paso el resultado que me muestra por pantalla:
root@linmame:~/MiMaca/svgalib-1.9.20# make install
Removing textmode utilities...
Removing shared library stubs (old & current)...
Removing shared library images (old & current)...
Removing static libraries...
Removing header files...
(cd doc; make -f /root/MiMaca/svgalib-1.9.20/doc/Makefile SRCDIR="/root/MiMaca/svgalib-1.9.20" uninstall)
make[1]: se ingresa al directorio `/root/MiMaca/svgalib-1.9.20/doc'
Removing all svgalib man pages.
make[1]: se sale del directorio `/root/MiMaca/svgalib-1.9.20/doc'
Installing header files in /usr/local/include.
(cd sharedlib/; \
make -f /root/MiMaca/svgalib-1.9.20/src/Makefile libvga.so.1.9.20 \
SRCDIR="/root/MiMaca/svgalib-1.9.20" DLLFLAGS="-fPIC" \
)
make[1]: se ingresa al directorio `/root/MiMaca/svgalib-1.9.20/sharedlib'
make[1]: `libvga.so.1.9.20' está actualizado.
make[1]: se sale del directorio `/root/MiMaca/svgalib-1.9.20/sharedlib'
(cd sharedlib/; \
make -f /root/MiMaca/svgalib-1.9.20/gl/Makefile libvgagl.so.1.9.20 \
SRCDIR="/root/MiMaca/svgalib-1.9.20" DLLFLAGS="-fPIC" \
)
make[1]: se ingresa al directorio `/root/MiMaca/svgalib-1.9.20/sharedlib'
make[1]: `libvgagl.so.1.9.20' está actualizado.
make[1]: se sale del directorio `/root/MiMaca/svgalib-1.9.20/sharedlib'
Removing shared library images (old & current)...
Installing shared library image as /usr/local/lib/libvga.so.1.9.20 /usr/local/lib/libvgagl.so.1.9.20.
Installing default keymap file in /etc/vga.
(cd utils; \
make -f /root/MiMaca/svgalib-1.9.20/utils/Makefile SRCDIR="/root/MiMaca/svgalib-1.9.20")
make[1]: se ingresa al directorio `/root/MiMaca/svgalib-1.9.20/utils'
make[1]: No se hace nada para `all'.
make[1]: se sale del directorio `/root/MiMaca/svgalib-1.9.20/utils'
(cd lrmi-0.6m;\
make)
make[1]: se ingresa al directorio `/root/MiMaca/svgalib-1.9.20/lrmi-0.6m'
make[1]: No se hace nada para `all'.
make[1]: se sale del directorio `/root/MiMaca/svgalib-1.9.20/lrmi-0.6m'
Installing textmode utilities in /usr/local/bin:
restorefont: Save/restore textmode font.
restorepalette: Set standard VGA palette.
dumpreg: Write ASCII dump of SVGA registers.
restoretextmode: Save/restore textmode registers.
textmode: Script that tries to restore textmode.
savetextmode: Script that saves textmode information used by 'textmode'.
mode3: Restore textmode by setting VESA mode 3.
Installing keymap utilities in /usr/local/bin:
svgakeymap: Perl script that generates scancode conversion maps.
(cd doc; make -f /root/MiMaca/svgalib-1.9.20/doc/Makefile SRCDIR="/root/MiMaca/svgalib-1.9.20" install )
make[1]: se ingresa al directorio `/root/MiMaca/svgalib-1.9.20/doc'
for dir in man?; do\
echo gzipping manpages in $dir;\
for file in $dir/*; do \
gzip $file; \
done; \
done
gzipping manpages in man1
gzipping manpages in man3
gzipping manpages in man5
gzipping manpages in man6
gzipping manpages in man7
gzipping manpages in man8
mkdir -p /usr/local/man/man1 /usr/local/man/man3 /usr/local/man/man5 \
/usr/local/man/man6 /usr/local/man/man7 /usr/local/man/man8
install -c -m 644 -o root -g root ../doc/man1/* /usr/local/man/man1
install -c -m 644 -o root -g root ../doc/man3/* /usr/local/man/man3
install -c -m 644 -o root -g root ../doc/man5/* /usr/local/man/man5
install -c -m 644 -o root -g root ../doc/man6/* /usr/local/man/man6
install -c -m 644 -o root -g root ../doc/man7/* /usr/local/man/man7
install -c -m 644 -o root -g root ../doc/man8/* /usr/local/man/man8
for dir in man? ; do \
echo gunzipping manpages in $dir;\
for file in $dir/*; do \
gunzip $file; \
done; \
done
gunzipping manpages in man1
gunzipping manpages in man3
gunzipping manpages in man5
gunzipping manpages in man6
gunzipping manpages in man7
gunzipping manpages in man8
make[1]: se sale del directorio `/root/MiMaca/svgalib-1.9.20/doc'
(cd kernel/svgalib_helper ; make default modules_install )
grep: /lib/modules/2.6.15-26-386/build/include/linux/device.h: No existe el fichero ó directorio
make[1]: se ingresa al directorio `/root/MiMaca/svgalib-1.9.20/kernel/svgalib_helper'
make -C /lib/modules/2.6.15-26-386/build SUBDIRS=/root/MiMaca/svgalib-1.9.20/kernel/svgalib_helper CLASS_CFLAGS= modules
make: se ingresa a un directorio desconocido
make: *** /lib/modules/2.6.15-26-386/build: No existe el fichero ó directorio. Alto.
make: se sale del directorio desconocido
make[1]: *** [default] Error 2
make[1]: se sale del directorio `/root/MiMaca/svgalib-1.9.20/kernel/svgalib_helper'
make: *** [installmodule] Error 2

A ver si hay alguna solución. Espero tus comentarios.

Un saludo