x86/cpufeatures: Add FEATURE_ZEN

x86/cpufeatures: Add FEATURE_ZEN

Add a ZEN feature bit so family-dependent static_cpu_has() optimizations
can be built for ZEN.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Orabug: 28063992
CVE: CVE-2018-3639

(cherry picked from commit d1035d97)
Signed-off-by: Mihai Carabas <mihai.carabas@oracle.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Signed-off-by: Brian Maly <brian.maly@oracle.com>
Conflicts:
	arch/x86/include/asm/cpufeatures.h
[Different filename and differnet bit for FEATURE_ZEN]

Signed-off-by: Brian Maly <brian.maly@oracle.com>