* geninitheader.sh: Process file specified in first parameter rather
than hardcoding grub_modules_init.lst.
* geninit.sh: Likewise. Also, construct header name dynamicaly rather
than hardcoding grub_modules_init.h.
* conf/common.rmk: Rename grub_modules_init.[ch] files associated with
grub-emu to grub_emu_init.[ch]. Add rules to build analogous
grub_probe_init.[ch] and grub_setup_init.[ch].
* conf/powerpc-ieee1275.rmk (grub_emu_DEPENDENCIES): Replace
grub_modules_init.h with grub_emu_init.h.
(grub_probe_DEPENDENCIES, grub_probe_SOURCES): Add new
grub_probe_init.[ch] files.
* conf/i386-efi.rmk: Likewise.
* conf/i386-pc.rmk: Likewise.
(grub_setup_DEPENDENCIES, grub_setup_SOURCES): Add new
grub_setup_init.[ch] files.
* util/grub-emu.c: Replace grub_modules_init.h with grub_emu_init.h.
* util/grub-probe.c: Include grub_probe_init.h. Use grub_init_all()
to initialize modules rather than a list of hardcoded functions.
* util/i386/pc/grub-setup.c: Include grub_setup_init.h. Use
grub_init_all() to initialize modules rather than a list of hardcoded
functions.