Use trad_frame_set_reg_addr for FreeBSD arm signal trampoline unwinders.

Use trad_frame_set_reg_addr for FreeBSD arm signal trampoline unwinders.

Replace individual calls to trad_frame_set_reg_addr for the general
purpose and floating point registers in signal trampoline frames used
by FreeBSD/aarch64 and FreeBSD/arm with calls to
trad_frame_set_reg_addr using the register maps for the corresponding
register sets.

gdb/ChangeLog:

	* aarch64-fbsd-tdep.c (aarch64_fbsd_gregmap)
	(aarch64_fbsd_fpregmap): Move earlier.
	(AARCH64_MCONTEXT_REG_SIZE, AARCH64_MCONTEXT_FPREG_SIZE): Delete.
	(aarch64_fbsd_sigframe_init): Use trad_frame_set_reg_regmap
	instead of individual calls to trad_frame_set_reg_addr.
	* arm-fbsd-tdep.c (arm_fbsd_gregmap, arm_fbsd_vfpregmap): Move
	earlier.
	(ARM_MCONTEXT_REG_SIZE, ARM_MCONTEXT_VFP_REG_SIZE): Delete.
	(arm_fbsd_sigframe_init): Use trad_frame_set_reg_regmap
	instead of individual calls to trad_frame_set_reg_addr.