Remove gdbarch_remote_breakpoint_from_pc

This patch removes gdbarch method remote_breakpoint_from_pc, as it
is no longer used.

gdb:

2016-11-03  Yao Qi  <yao.qi@linaro.org>

	* arch-utils.c (default_remote_breakpoint_from_pc): Remove.
	* arch-utils.h (default_remote_breakpoint_from_pc): Remove.
	* arm-tdep.c (arm_remote_breakpoint_from_pc): Remove.
	(arm_gdbarch_init): Don't call
	set_gdbarch_remote_breakpoint_from_pc.
	* gdbarch.sh (remote_breakpoint_from_pc): Remove.
	* gdbarch.c, gdbarch.h: Regenerate.
	* mips-tdep.c (mips_remote_breakpoint_from_pc): Remove.
	(mips_gdbarch_init): Don't call
	set_gdbarch_remote_breakpoint_from_pc.