i386: Add the support for AMD EPYC 3rd generation processors

i386: Add the support for AMD EPYC 3rd generation processors

Adds the support for AMD 3rd generation processors. The model
display for the new processor will be EPYC-Milan.

Adds the following new feature bits on top of the feature bits from
the first and second generation EPYC models.

pcid          : Process context identifiers support
ibrs          : Indirect Branch Restricted Speculation
ssbd          : Speculative Store Bypass Disable
erms          : Enhanced REP MOVSB/STOSB support
fsrm          : Fast Short REP MOVSB support
invpcid       : Invalidate processor context ID
pku           : Protection keys support
svme-addr-chk : SVM instructions address check for #GP handling

Depends on the following kernel commits:
14c2bf81fcd2 ("KVM: SVM: Fix #GP handling for doubly-nested virtualization")
3b9c723ed7cf ("KVM: SVM: Add support for SVM instruction address check change")
4aa2691dcbd3 ("8ce1c461188799d863398dd2865d KVM: x86: Factor out x86 instruction emulation with decoding")
4407a797e941 ("KVM: SVM: Enable INVPCID feature on AMD")
9715092f8d7e ("KVM: X86: Move handling of INVPCID types to x86")
3f3393b3ce38 ("KVM: X86: Rename and move the function vmx_handle_memory_failure to x86.c")
830bd71f2c06 ("KVM: SVM: Remove set_cr_intercept, clr_cr_intercept and is_cr_intercept")
4c44e8d6c193 ("KVM: SVM: Add new intercept word in vmcb_control_area")
c62e2e94b9d4 ("KVM: SVM: Modify 64 bit intercept field to two 32 bit vectors")
9780d51dc2af ("KVM: SVM: Modify intercept_exceptions to generic intercepts")
30abaa88382c ("KVM: SVM: Change intercept_dr to generic intercepts")
03bfeeb988a9 ("KVM: SVM: Change intercept_cr to generic intercepts")
c45ad7229d13 ("KVM: SVM: Introduce vmcb_(set_intercept/clr_intercept/_is_intercept)")
a90c1ed9f11d ("(pcid) KVM: nSVM: Remove unused field")
fa44b82eb831 ("KVM: x86: Move MPK feature detection to common code")
38f3e775e9c2 ("x86/Kconfig: Update config and kernel doc for MPK feature on AMD")
37486135d3a7 ("KVM: x86: Fix pkru save/restore when guest CR4.PKE=0, move it to x86.c")

Signed-off-by: Babu Moger <babu.moger@amd.com>
Message-Id: <161290460478.11352.8933244555799318236.stgit@bmoger-ubuntu>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>