x86/cpuid: update signature of hvm_cr4_guest_valid_bits()

x86/cpuid: update signature of hvm_cr4_guest_valid_bits()

With the new cpuid infrastructure there is a domain-wide struct cpuid
policy and there is no need to pass a separate struct vcpu * into
hvm_cr4_guest_valid_bits() anymore. Make the function accept struct
domain * instead and update callers.

Signed-off-by: Sergey Dyasli <sergey.dyasli@citrix.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>