Split-up -march=icelake on -march=icelake-server and -march=icelake-client
gcc/
	* config.gcc (icelake-client, icelake-server): New.
	(icelake): Remove.
	* config/i386/i386.c (initial_ix86_tune_features): Extend to 64 bit.
	(initial_ix86_arch_features): Ditto.
	(PTA_SKYLAKE): Add SGX.
	(PTA_ICELAKE): Remove.
	(PTA_ICELAKE_CLIENT): New.
	(PTA_ICELAKE_SERVER): New.
	(ix86_option_override_internal): Split up icelake on icelake client and
	icelake server.
	(get_builtin_code_for_version): Ditto.
	(fold_builtin_cpu): Ditto.
	* config/i386/driver-i386.c (config/i386/driver-i386.c): Ditto.
	* config/i386/i386-c.c (ix86_target_macros_internal): Ditto
	* config/i386/i386.h (processor_type): Ditto.
	* doc/invoke.texi: Ditto.

gcc/testsuite/
	* g++.dg/ext/mv16.C: Split up icelake on icelake client and
	icelake-server.
	* gcc.target/i386/funcspec-56.inc: Ditto.

libgcc/
	* config/i386/cpuinfo.h (processor_subtypes): Split up icelake on
	icelake-client and icelake-server.

From-SVN: r258518