KVM: x86: allow compiling as non-module with W=1

Compile error with CONFIG_KVM_INTEL=y and W=1:

  CC      arch/x86/kvm/vmx/vmx.o
arch/x86/kvm/vmx/vmx.c:68:32: error: 'vmx_cpu_id' defined but not used [-Werror=unused-const-variable=]
   68 | static const struct x86_cpu_id vmx_cpu_id[] = {
      |                                ^~~~~~~~~~
cc1: all warnings being treated as errors

When building with =y, the MODULE_DEVICE_TABLE macro doesn't generate a
reference to the structure (or any code at all).  This makes W=1 compiles
unhappy.

Wrap both in a #ifdef to avoid the issue.

Signed-off-by: Valdis Kletnieks <valdis.kletnieks@vt.edu>
[Do the same for CONFIG_KVM_AMD. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Author: valdisk

arch/x86/kvm/svm.c

@@ -57,11 +57,13 @@
 MODULE_AUTHOR("Qumranet");
 MODULE_LICENSE("GPL");
 
+#ifdef MODULE
 static const struct x86_cpu_id svm_cpu_id[] = {
 	X86_FEATURE_MATCH(X86_FEATURE_SVM),
 	{}
 };
 MODULE_DEVICE_TABLE(x86cpu, svm_cpu_id);
+#endif
 
 #define IOPM_ALLOC_ORDER 2
 #define MSRPM_ALLOC_ORDER 1

arch/x86/kvm/vmx/vmx.c

@@ -64,11 +64,13 @@
 MODULE_AUTHOR("Qumranet");
 MODULE_LICENSE("GPL");
 
+#ifdef MODULE
 static const struct x86_cpu_id vmx_cpu_id[] = {
 	X86_FEATURE_MATCH(X86_FEATURE_VMX),
 	{}
 };
 MODULE_DEVICE_TABLE(x86cpu, vmx_cpu_id);
+#endif
 
 bool __read_mostly enable_vpid = 1;
 module_param_named(vpid, enable_vpid, bool, 0444);