Fix the mask for the sqrdml(a|s)h instructions.

Fix the mask for the sqrdml(a|s)h instructions.

Rn is supposed to have a 5 bit range but instead was given 4 bits
causing these instructions to disassemble as unknown instructions.

opcodes/

	* aarch64-tbl.h (sqrdmlah, sqrdmlsh): Fix masks.

gas/

	* testsuite/gas/aarch64/rdma.s: Test for larger register numbers.
	* testsuite/gas/aarch64/rdma.d: Update results.
	* testsuite/gas/aarch64/rdma-directive.d: Likewise.