the i386 does. The previous definition was a SunOS-specific hack,
and if that is really still needed somwhere, it can still be used
by defining sigtramp_saved_pc as m68k_sigtramp_saved_pc in the
target-specific tm.h file. The common sigtramp_saved_pc() fucntion
uses SIGCONTEXT_PC_OFFSET to find the return PC (the best way).
Do not define SIG_PC_FP_OFFSET here. (very machine-specific!)