kvm: vmx: fix some -Wmissing-prototypes warnings

We get some warnings when building kernel with W=1:
arch/x86/kvm/vmx/vmx.c:426:5: warning: no previous prototype for ‘kvm_fill_hv_flush_list_func’ [-Wmissing-prototypes]
arch/x86/kvm/vmx/nested.c:58:6: warning: no previous prototype for ‘init_vmcs_shadow_fields’ [-Wmissing-prototypes]

Make them static to fix this.
Signed-off-by: Yi Wang <wang.yi59@zte.com.cn>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

arch/x86/kvm/vmx/nested.c

@@ -55,7 +55,7 @@ static u16 shadow_read_write_fields[] = {
 static int max_shadow_read_write_fields =
 	ARRAY_SIZE(shadow_read_write_fields);
 
-void init_vmcs_shadow_fields(void)
+static void init_vmcs_shadow_fields(void)
 {
 	int i, j;
 

arch/x86/kvm/vmx/vmx.c

@@ -423,7 +423,7 @@ static void check_ept_pointer_match(struct kvm *kvm)
 	to_kvm_vmx(kvm)->ept_pointers_match = EPT_POINTERS_MATCH;
 }
 
-int kvm_fill_hv_flush_list_func(struct hv_guest_mapping_flush_list *flush,
+static int kvm_fill_hv_flush_list_func(struct hv_guest_mapping_flush_list *flush,
 		void *data)
 {
 	struct kvm_tlb_range *range = data;