S/390: Add ipte/idte variants with optional operands

S/390: Add ipte/idte variants with optional operands

This patch adds missing variants of ipte and idte instructions added with later CPU
generations.

ipte got an optional operand with z196 and another one with zEC12.
idte got an optional operand with zEC12

opcodes/ChangeLog:

2017-05-30  Andreas Krebbel  <krebbel@linux.vnet.ibm.com>

	* s390-opc.c: Add new idte/ipte variants.
	* s390-opc.txt: Likewise.

gas/ChangeLog:

2017-05-30  Andreas Krebbel  <krebbel@linux.vnet.ibm.com>

	* testsuite/gas/s390/zarch-z196.d: Add new idte/ipte variants.
	* testsuite/gas/s390/zarch-z196.s: Likewise.
	* testsuite/gas/s390/zarch-zEC12.d: Likewise.
	* testsuite/gas/s390/zarch-zEC12.s: Likewise.