[ARC] Add SYNTAX_NOP and SYNTAX_1OP for extension instructions

[ARC] Add SYNTAX_NOP and SYNTAX_1OP for extension instructions

gas/
2016-05-03  Claudiu Zissulescu  <claziss@synopsys.com>

	* config/tc-arc.c (syntaxclass): Add SYNTAX_NOP and SYNTAX_1OP.
	(arc_extinsn): Handle new introduced syntax.
	* testsuite/gas/arc/textinsn1op.d: New file.
	* testsuite/gas/arc/textinsn1op.s: Likewise.
	* doc/c-arc.texi: Document SYNTAX_NOP and SYNTAX_1OP.

opcodes/
2016-05-03  Claudiu Zissulescu  <claziss@synopsys.com>

	* arc-ext.c (dump_ARC_extmap): Handle SYNATX_NOP and SYNTAX_1OP.
	(arcExtMap_genOpcode): Likewise.
	* arc-opc.c (arg_32bit_rc): Define new variable.
	(arg_32bit_u6): Likewise.
	(arg_32bit_limm): Likewise.

include/
2016-05-03  Claudiu Zissulescu  <claziss@synopsys.com>

	* opcode/arc.h (ARC_SYNTAX_1OP): Declare
	(ARC_SYNTAX_NOP): Likewsie.
	(ARC_OP1_MUST_BE_IMM): Update defined value.
	(ARC_OP1_IMM_IMPLIED): Likewise.
	(arg_32bit_rc, arg_32bit_u6, arg_32bit_limm): Declare.