Move fixup fx_bit_fixP and fx_im_disp fields to TC_FIX_TYPE

Move fixup fx_bit_fixP and fx_im_disp fields to TC_FIX_TYPE

These are only used by dlx and ns32k.

	* write.h: Don't include bit_fix.h.
	(struct fix): Rearrange some fields.  Delete fx_im_disp and
	fx_bit_fixP.  Use bitfields for fx_size and fx_pcrel_adjust.
	* write.c (fix_new_internal): Don't init fx_im_disp and fx_bit_fixP.
	(fixup_segment): Don't exclude overflow checks on fx_bit_fixP.
	(print_fixup): Don't print im_disp.
	* config/tc-cris.c (md_apply_fix): Remove tests of fx_bit_fixP
	and fx_im_disp.
	* config/tc-dlx.c (md_apply_fix): Remove wrong debug code.  Set
	fx_no_overflow when fx_bit_fixP.
	* config/tc-dlx.h: Include bit_fix.h.
	(TC_FIX_TYPE, tc_fix_data, TC_INIT_FIX_DATA): Define.
	* config/tc-ns32k.c (fix_new_ns32k, fix_new_ns32k_exp): Set
	fx_no_overflow when bit_fixP.
	* config/tc-ns32k.h (TC_FIX_TYPE): Add fx_bit_fixP and fx_im_disp.
	(fix_im_disp, fix_bit_fixP): Adjust to suit.
	(TC_INIT_FIX_DATA, TC_FIX_DATA_PRINT): Likewise.