arc: Cleanup addsi3 instruction pattern

arc: Cleanup addsi3 instruction pattern

This patch repurposes the code letter 's' to 'x', and 'S' to 'J'.
Also it introduces new CODE letters 'x', 's', 'S', and 'N'.

gcc/ChangeLog:

	* config/arc/arc-protos.h (arc_output_addsi): Remove declaration.
	(split_addsi): Likewise.
	* config/arc/arc.cc (arc_print_operand): Add/repurpose 's', 'S',
	'N', 'x', and 'J' code letters.
	(arc_output_addsi): Make it static.
	(split_addsi): Remove it.
	* config/arc/arc.h (UNSIGNED_INT*): New defines.
	(SINNED_INT*): Likewise.
	* config/arc/arc.md (type): Add add, sub, bxor types.
	(tst_movb): Change code letter from 's' to 'x'.
	(andsi3_i): Likewise.
	(addsi3_mixed): Refurbish the pattern.
	(call_i): Change code letter from 'S' to 'J'.
	* config/arc/arc700.md: Add newly introduced types.
	* config/arc/arcHS.md: Likewsie.
	* config/arc/arcHS4x.md: Likewise.
	* config/arc/constraints.md (Cca, CL2, Csp, C2a): Remove it.
	(CM4): Update description.
	(CP4, C6u, C6n, CIs, C4p): New constraint.

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