* config/obj-coff.h, config/obj-coff.c: Deleted all code used only when

* config/obj-coff.h, config/obj-coff.c: Deleted all code used only when
BFD_ASSEMBLER is not defined, and all conditionals relating to such code.  No
such targets remain.

Fixes for stabs-in-coff:
* config/obj-coff.c: Include subsegs.h.
(coff_frob_section): New function.
(obj_coff_init_stab_section): New function.
* config/obj-coff.h (obj_coff_init_stab_section, coff_frob_section): Declare.
(obj_frob_section): New macro; uses coff_frob_section.
(INIT_STAB_SECTION): New macro; uses obj_coff_init_stab_section.