arc: Remove unused/incomplete alignment assembly annotation.

arc: Remove unused/incomplete alignment assembly annotation.

Removes '&' print operant punct character, disable -mannotate-align
option and clean up the port.

gcc/

	* config/arc/arc-protos.h (arc_clear_unalign): Remove.
	(arc_toggle_unalign): Likewise.
	* config/arc/arc.cc (machine_function) Remove unalign.
	(arc_init): Remove `&` punct character.
	(arc_print_operand): Remove `&` related functions.
	(arc_verify_short): Update function's number of parameters.
	(output_short_suffix): Update function.
	(arc_short_long): Likewise.
	(arc_clear_unalign): Remove.
	(arc_toggle_unalign): Likewise.
	* config/arc/arc.h (ASM_OUTPUT_CASE_END): Remove.
	(ASM_OUTPUT_ALIGN): Update.
	* config/arc/arc.md: Remove all `%&` references.
	* config/arc/arc.opt (mannotate-align): Ignore option.
	* doc/invoke.texi (mannotate-align): Update description.

Signed-off-by: Claudiu Zissulescu <claziss@gmail.com>