S/390: Deprecate g5 and g6 CPU levels

S/390: Deprecate g5 and g6 CPU levels

gcc/ChangeLog:

2015-12-18  Andreas Krebbel  <krebbel@linux.vnet.ibm.com>

	* config/s390/driver-native.c (s390_host_detect_local_cpu): Pick
	z900 -march -mtune even on g5 and g6 machines.
	* config/s390/s390.c (s390_option_override_internal): New argument
	to distingiush between options and target attributes.  Emit
	deprecation warning for g5 and g6 arch/tune options.
	(s390_option_override): Set new s390_option_override_internal
	argument to true.
	(s390_valid_target_attribute_tree): Set new
	s390_option_override_internal argument to false.
	* config/s390/s390.h: Default to z900 in the driver.
	* doc/invoke.texi: Document the deprecation of g5 and g6.

gcc/testsuite/ChangeLog:

2015-12-18  Andreas Krebbel  <krebbel@linux.vnet.ibm.com>

	* gcc.target/s390/hotpatch-8.c: Add -Wno-deprecated to options.
	* gcc.target/s390/hotpatch-9.c: Likewise.

From-SVN: r231806