KVM: Enable DRNG feature support for KVM

This patch exposes DRNG feature to KVM guests.

The RDRAND instruction can provide software with sequences of
random numbers generated from white noise.
Signed-off-by: NYang, Wei <wei.y.yang@intel.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

arch/x86/kvm/x86.c

@@ -2345,7 +2345,7 @@ static void do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function,
 		0 /* Reserved, DCA */ | F(XMM4_1) |
 		F(XMM4_2) | F(X2APIC) | F(MOVBE) | F(POPCNT) |
 		0 /* Reserved*/ | F(AES) | F(XSAVE) | 0 /* OSXSAVE */ | F(AVX) |
-		F(F16C);
+		F(F16C) | F(RDRAND);
 	/* cpuid 0x80000001.ecx */
 	const u32 kvm_supported_word6_x86_features =
 		F(LAHF_LM) | F(CMP_LEGACY) | 0 /*SVM*/ | 0 /* ExtApicSpace */ |