* i386nbsd-tdep.c: Include "trad-frame.h" and "tramp-frame.h"

* i386nbsd-tdep.c: Include "trad-frame.h" and "tramp-frame.h"
(sigtramp_retcode, i386nbsd_sigtramp_offset, i386nbsd_sigtramp_p):
Remove
(i386nbsd_mc_reg_offset): New array.
(i386nbsd_sigtramp_cache_init): New function.
(i386nbsd_sigtramp_sc16, i386nbsd_sigtramp_sc2, i386nbsd_sigtramp_si2)
(i386nbsd_sigtramp_si31, i386nbsd_sigtramp_si4): New signal trampoline
frame descriptions.
(i386nbsd_init_abi): Override ABI sigcontext defaults and register
new signal frame unwinders
* Makefile.in (i386nbsd-tdep.o): Update dependencies.
* tramp-frame.h (struct tramp_frame): Allow for 48 instructions