[binutils][aarch64] New SVE_SHLIMM_UNPRED_22 operand.

[binutils][aarch64] New SVE_SHLIMM_UNPRED_22 operand.

New operand describes a shift-left immediate encoded in bits
22:20-19:18-16 where UInt(bits) - esize == shift.
This operand is useful for instructions like sshllb.

gas/ChangeLog:

2019-05-09  Matthew Malcomson  <matthew.malcomson@arm.com>

	* config/tc-aarch64.c (parse_operands): Handle new SVE_SHLIMM_UNPRED_22
	operand.

include/ChangeLog:

2019-05-09  Matthew Malcomson  <matthew.malcomson@arm.com>

	* opcode/aarch64.h (enum aarch64_opnd): New SVE_SHLIMM_UNPRED_22
	operand.

opcodes/ChangeLog:

2019-05-09  Matthew Malcomson  <matthew.malcomson@arm.com>

	* aarch64-asm-2.c: Regenerated.
	* aarch64-dis-2.c: Regenerated.
	* aarch64-opc-2.c: Regenerated.
	* aarch64-opc.c (operand_general_constraint_met_p): Constraint checking
	for SVE_SHLIMM_UNPRED_22.
	(aarch64_print_operand): Add printing for SVE_SHLIMM_UNPRED_22.
	* aarch64-tbl.h (AARCH64_OPERANDS): Use new SVE_SHLIMM_UNPRED_22
	operand.