KVM: x86: clean up a return

Returning a literal X86EMUL_CONTINUE is slightly clearer than returning
rc.

Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Link: https://lore.kernel.org/r/7604cbbf-15e6-45a8-afec-cf5be46c2924@stanley.mountain
Signed-off-by: Sean Christopherson <seanjc@google.com>

arch/x86/kvm/x86.c

@@ -8021,7 +8021,7 @@ static int emulator_read_write(struct x86_emulate_ctxt *ctxt,
 		return rc;
 
 	if (!vcpu->mmio_nr_fragments)
-		return rc;
+		return X86EMUL_CONTINUE;
 
 	gpa = vcpu->mmio_fragments[0].gpa;