BSD_SETJMP or BSD__SETJMP is defined, resp.
* sysdeps/m68k/bsd-setjmp.c: Inline setjmp code instead of making
a tail call to __sigsetjmp that would require extending the
caller's frame.
* sysdeps/m68k/bsd-_setjmp.c: Likewise.
* sysdeps/m68k/bsd-setjmp.S: Deleted.
* sysdeps/m68k/bsd-_setjmp.S: Deleted.