Changes for a `m88k-motorola-sysv3'

[Jim Wilson]

m88k/dolph.h includes m88k/sysv3.h.  I think the right way to fix this is
to move the definition of INITIALIZE_TRAMPOLINE from dolph.h to sysv3.h,
and then change libgcc2.c to check __sysV88__ instead of __DOLPHIN__
(both the dolph.h and sysv3.h ports define __sysB88__).

If you want to make this prettier, copy the FINALIZE_TRAMPOLINE stuff
from the m68k port, and use it instead of redefining INITIALIZE_TRAMPOLINE.

Jim