Implements aarch64 process record and reverse debugging support

Implements aarch64 process record and reverse debugging support

This patch adds the support of aarch64-linux process record and reverse
debugging.  The implementation is similar to ARM's counterpart.

2015-05-26  Omair Javaid  <omair.javaid@linaro.org>
	    Yao Qi  <yao.qi@linaro.org>

	* aarch64-linux-tdep.c: Include linux-record.h and
	record-full.h.
	(struct linux_record_tdep aarch64_linux_record_tdep): Declare.
	(aarch64_syscall): New enum.
	(aarch64_canonicalize_syscall): New function.
	(aarch64_all_but_pc_registers_record): New function.
	(aarch64_linux_syscall_record): New function.
	(aarch64_linux_init_abi): Install AArch64 process record
	handler.  Update to handle syscall recording.
	* aarch64-tdep.c: Include record.h and record-full.h.
	(submask, bit, bits, REG_ALLOC, MEM_ALLOC): New macros.
	(struct aarch64_mem_r): Define.
	(aarch64_record_result): New enum.
	(struct insn_decode_record): Define.
	(insn_decode_record): New typedef.
	(aarch64_record_data_proc_reg): New function.
	(aarch64_record_data_proc_imm): New function.
	(aarch64_record_branch_except_sys): New function.
	(aarch64_record_load_store): New function.
	(aarch64_record_data_proc_simd_fp): New function.
	(aarch64_record_asimd_load_store): New function.
	(aarch64_record_decode_insn_handler): New function.
	(deallocate_reg_mem): New function.
	(aarch64_process_record): New function.
	* aarch64-tdep.h (struct gdbarch_tdep) <aarch64_syscall_record>:
	New field.
	(aarch64_process_record): New extern declaration.
	* configure.tgt: Add linux-record.o to gdb_target_obs.
	* linux-record.h (struct linux_record_tdep) <arg7>: New field.