* arm-tdep.c: Include frame-unwind.h, frame-base.h, and
trad-frame.h.
(arm_get_cache): Delete macro.
(struct arm_prologue_cache): Update comments. Make saved_regs into
a trad_frame_saved_reg pointer. Remove unwound_pc; rename unwound_sp
to prev_sp.
(thumb_scan_prologue): Update for cache changes. Don't call
DEPRECATED_PC_IN_CALL_DUMMY.
(arm_scan_prologue): Update for cache changes. Take NEXT_FRAME
argument and use it in desperation search for our prologue. Do not
search past the specified PC.
(arm_make_prologue_cache): Simplify.