x86/nestedhvm: Inline nestedhvm_vcpu_in_guestmode()

This function just returns vcpu_nestedhvm(v).nv_guestmode and would
be better inlined to improve codegen.

Signed-off-by: Teddy Astie <teddy.astie@vates.tech>
Acked-by: Jan Beulich <jbeulich@suse.com>

xen/arch/x86/hvm/nestedhvm.c

@@ -15,13 +15,6 @@
 
 static unsigned long *shadow_io_bitmap[3];
 
-/* Nested VCPU */
-bool
-nestedhvm_vcpu_in_guestmode(struct vcpu *v)
-{
-    return vcpu_nestedhvm(v).nv_guestmode;
-}
-
 void
 nestedhvm_vcpu_reset(struct vcpu *v)
 {

xen/arch/x86/include/asm/hvm/nestedhvm.h

@@ -28,11 +28,14 @@ static inline bool nestedhvm_enabled(const struct domain *d)
     return IS_ENABLED(CONFIG_HVM) && (d->options & XEN_DOMCTL_CDF_nested_virt);
 }
 
-/* Nested VCPU */
+static inline bool nestedhvm_vcpu_in_guestmode(const struct vcpu *v)
+{
+    return vcpu_nestedhvm(v).nv_guestmode;
+}
+
 int nestedhvm_vcpu_initialise(struct vcpu *v);
 void nestedhvm_vcpu_destroy(struct vcpu *v);
 void nestedhvm_vcpu_reset(struct vcpu *v);
-bool nestedhvm_vcpu_in_guestmode(struct vcpu *v);
 #define nestedhvm_vcpu_enter_guestmode(v) \
     vcpu_nestedhvm(v).nv_guestmode = 1
 #define nestedhvm_vcpu_exit_guestmode(v)  \