(arm_psr_thumb_bit): New. Update all uses of CPSR_T to
call this function.
(arm_pc_is_thumb): Add a gdbarch argument. Update all callers.
Check is_m after force-mode.
(arm_gdbarch_init): Check the binary before the target description.
Add check for M profile attribute. If we have an M-profile device,
but no target register description, use arm-with-m. Recognize the
new org.gnu.gdb.arm.m-profile feature and its xpsr register.
(_initialize_arm_tdep): Call initialize_tdesc_arm_with_m.
* arm-tdep.h (XPSR_T): Define.
(struct gdbarch_tdep): Add is_m member.
* features/arm-m-profile.xml, features/arm-with-m.c,
features/arm-with-m.xml: New files.
doc/
* gdb.texinfo (ARM Features): Document
org.gnu.gdb.arm.m-profile.
