x86/cpufeatures: Enable a new AVX512 CPU feature

Add a new AVX512 instruction group/feature for enumeration in
/proc/cpuinfo: AVX512_VP2INTERSECT.

CPUID.(EAX=7,ECX=0):EDX[bit 8]  AVX512_VP2INTERSECT

Detailed information of CPUID bits for this feature can be found in
the Intel Architecture Intsruction Set Extensions Programming Reference
document (refer to Table 1-2). A copy of this document is available at
https://bugzilla.kernel.org/show_bug.cgi?id=204215.

Signed-off-by: Gayatri Kammela <gayatri.kammela@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190717234632.32673-3-gayatri.kammela@intel.com