KVM: x86: Move bit() helper to cpuid.h

Move bit() to cpuid.h in preparation for incorporating the reverse_cpuid
array in bit() build-time assertions.  Opportunistically use the BIT()
macro instead of open-coding the shift.

No functional change intended.
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

arch/x86/kvm/cpuid.h

@@ -55,6 +55,11 @@ static const struct cpuid_reg reverse_cpuid[] = {
 	[CPUID_7_EDX]         = {         7, 0, CPUID_EDX},
 };
 
+static inline u32 bit(int bitno)
+{
+	return BIT(bitno & 31);
+}
+
 static __always_inline struct cpuid_reg x86_feature_cpuid(unsigned x86_feature)
 {
 	unsigned x86_leaf = x86_feature / 32;

arch/x86/kvm/x86.h

@@ -144,11 +144,6 @@ static inline bool is_pae_paging(struct kvm_vcpu *vcpu)
 	return !is_long_mode(vcpu) && is_pae(vcpu) && is_paging(vcpu);
 }
 
-static inline u32 bit(int bitno)
-{
-	return 1 << (bitno & 31);
-}
-
 static inline u8 vcpu_virt_addr_bits(struct kvm_vcpu *vcpu)
 {
 	return kvm_read_cr4_bits(vcpu, X86_CR4_LA57) ? 57 : 48;