Pass value * instead of bfd_byte * to pass_* functions in aarch64-tdep.c

Pass value * instead of bfd_byte * to pass_* functions in aarch64-tdep.c

This patch changes the last argument of functions pass_in_x_or_stack,
pass_in_v_or_stack, pass_on_stack, and pass_in_x to type value *.

gdb:

2015-11-16  Yao Qi  <yao.qi@linaro.org>

	* aarch64-tdep.c (pass_in_x_or_stack): Change argument type
	from bfd_byte * to value *.  Caller updated.
	(pass_in_x): Likewise.
	(pass_in_v_or_stack): Likewise.
	(pass_on_stack): Likewise.