KVM: x86: Make kvm_mtrr_valid() static now that there are no external users

Make kvm_mtrr_valid() local to mtrr.c now that it's not used to check the
validity of a PAT MSR value.
Reviewed-by: Kai Huang <kai.huang@intel.com>
Link: https://lore.kernel.org/r/20230511233351.635053-8-seanjc@google.comSigned-off-by: Sean Christopherson <seanjc@google.com>

arch/x86/kvm/mtrr.c

@@ -65,7 +65,7 @@ static bool valid_mtrr_type(unsigned t)
 	return t < 8 && (1 << t) & 0x73; /* 0, 1, 4, 5, 6 */
 }
 
-bool kvm_mtrr_valid(struct kvm_vcpu *vcpu, u32 msr, u64 data)
+static bool kvm_mtrr_valid(struct kvm_vcpu *vcpu, u32 msr, u64 data)
 {
 	int i;
 	u64 mask;
@@ -100,7 +100,6 @@ bool kvm_mtrr_valid(struct kvm_vcpu *vcpu, u32 msr, u64 data)
 
 	return (data & mask) == 0;
 }
-EXPORT_SYMBOL_GPL(kvm_mtrr_valid);
 
 static bool mtrr_is_enabled(struct kvm_mtrr *mtrr_state)
 {

arch/x86/kvm/x86.h

@@ -309,7 +309,6 @@ void kvm_deliver_exception_payload(struct kvm_vcpu *vcpu,
 
 void kvm_vcpu_mtrr_init(struct kvm_vcpu *vcpu);
 u8 kvm_mtrr_get_guest_memory_type(struct kvm_vcpu *vcpu, gfn_t gfn);
-bool kvm_mtrr_valid(struct kvm_vcpu *vcpu, u32 msr, u64 data);
 int kvm_mtrr_set_msr(struct kvm_vcpu *vcpu, u32 msr, u64 data);
 int kvm_mtrr_get_msr(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata);
 bool kvm_mtrr_check_gfn_range_consistency(struct kvm_vcpu *vcpu, gfn_t gfn,