Move common aarch64 HW breakpoint/watchpoint code to nat/

Move common aarch64 HW breakpoint/watchpoint code to nat/

When I look at test fails related to watchpoint on aarch64-linux,
I find there are some code duplicates between GDB and GDBserver.
This patch is to move some of them to a nat/aarch64-linux-hw-point.{h,c}.

The only change I do is about the dr_changed_t typedef, which was
ULONGEST in GDB and 'unsigned long long' in GDBserver.  Each bit
of dr_changed_t represents a status of each HW breakpoint or
watchpoint register, and the max number of HW breakpoint or watchpoint
registers is 16, so the width of 'unsigned long long' is sufficient.

gdb:

2015-07-17  Yao Qi  <yao.qi@linaro.org>

	* Makefile.in (HFILES_NO_SRCDIR): Add
	nat/aarch64-linux-hw-point.h.
	(aarch64-linux-hw-point.o): New rule.
	* nat/aarch64-linux-hw-point.h: New file.
	* nat/aarch64-linux-hw-point.c: New file.
	* aarch64-linux-nat.c: Include nat/aarch64-linux-hw-point.h.
	(AARCH64_HBP_MAX_NUM): Move to nat/aarch64-linux-hw-point.h.
	(AARCH64_HWP_MAX_NUM, AARCH64_HBP_ALIGNMENT): Likewise.
	(AARCH64_HWP_ALIGNMENT): Likewise.
	(AARCH64_HWP_MAX_LEN_PER_REG): Likewise.
	(AARCH64_DEBUG_NUM_SLOTS, AARCH64_DEBUG_ARCH): Likewise.
	(AARCH64_DEBUG_ARCH_V8, DR_MARK_ALL_CHANGED): Likewise.
	(DR_MARK_N_CHANGED, DR_CLEAR_CHANGED): Likewise.
	(DR_HAS_CHANGED, DR_N_HAS_CHANGE): Likewise.
	(aarch64_num_bp_regs, aarch64_num_wp_regs): Likewise.
	(struct aarch64_debug_reg_state): Likewise.
	(struct arch_lwp_info):	Likewise.
	(aarch64_linux_set_debug_regs): Likewise.
	(aarch64_notify_debug_reg_change): Remove static.
	(aarch64_align_watchpoint): Likewise.
	(DR_CONTROL_ENABLED, DR_CONTROL_LENGTH): Likewise.
	(aarch64_watchpoint_length): Likewise.
	(aarch64_point_encode_ctrl_reg): Likewise
	(aarch64_point_is_aligned): Likewise.
	(aarch64_dr_state_insert_one_point): Likewise.
	(aarch64_dr_state_remove_one_point): Likewise.
	(aarch64_handle_breakpoint): Likewise.
	(aarch64_handle_aligned_watchpoint): Likewise.
	(aarch64_handle_unaligned_watchpoint): Likewise.
	(aarch64_handle_watchpoint): Likewise.
	* config/aarch64/linux.mh (NAT_FILE): Add
	aarch64-linux-hw-point.o.

gdb/gdbserver:

2015-07-17  Yao Qi  <yao.qi@linaro.org>

	* Makefile.in (aarch64-linux-hw-point.o): New rule.
	* configure.srv (srv_tgtobj): Append aarch64-linux-hw-point.o.
	* linux-aarch64-low.c: Include nat/aarch64-linux-hw-point.h.
	(AARCH64_HBP_MAX_NUM): Move to nat/aarch64-linux-hw-point.h.
	(AARCH64_HWP_MAX_NUM, AARCH64_HBP_ALIGNMENT): Likewise.
	(AARCH64_HWP_ALIGNMENT): Likewise.
	(AARCH64_HWP_MAX_LEN_PER_REG): Likewise.
	(AARCH64_DEBUG_NUM_SLOTS, AARCH64_DEBUG_ARCH): Likewise.
	(aarch64_num_bp_regs, aarch64_num_wp_regs): Likewise.
	(AARCH64_DEBUG_ARCH_V8, DR_MARK_ALL_CHANGED): Likewise.
	(DR_MARK_N_CHANGED, DR_CLEAR_CHANGED): Likewise.
	(DR_HAS_CHANGED, DR_N_HAS_CHANGE): Likewise.
	(struct aarch64_debug_reg_state): Likewise.
	(struct arch_lwp_info):	Likewise.
	(aarch64_align_watchpoint): Likewise.
	(DR_CONTROL_ENABLED, DR_CONTROL_LENGTH): Likewise.
	(aarch64_watchpoint_length): Likewise.
	(aarch64_point_encode_ctrl_reg): Likewise
	(aarch64_point_is_aligned): Likewise.
	(aarch64_align_watchpoint): Likewise.
	(aarch64_linux_set_debug_regs):
	(aarch64_dr_state_insert_one_point): Likewise.
	(aarch64_dr_state_remove_one_point): Likewise.
	(aarch64_handle_breakpoint): Likewise.
	(aarch64_handle_aligned_watchpoint): Likewise.
	(aarch64_handle_unaligned_watchpoint): Likewise.
	(aarch64_handle_watchpoint): Likewise.