m68k: use the mmu pci.h for m68knommu as well

The (m68knommu) COMEMPCI support has been removed from the kernel,
so now the mmu pci.h can be used on non-mmu setups as well.
Remove the non-mmu pci_no.h and revert the pci_mm.h to be pci.h.

Signed-off-by: Greg Ungerer <gerg@uclinux.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>