powerpc/pseries/vas: Remove the unneeded result variable

Return the value vas_register_coproc_api() directly instead of storing it
in another redundant variable.

Reported-by: Zeal Robot <zealci@zte.com.cn>
Signed-off-by: ye xingchen <ye.xingchen@zte.com.cn>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220825072657.229168-1-ye.xingchen@zte.com.cn

arch/powerpc/platforms/pseries/vas.c

@@ -501,14 +501,10 @@ static const struct vas_user_win_ops vops_pseries = {
 int vas_register_api_pseries(struct module *mod, enum vas_cop_type cop_type,
 			     const char *name)
 {
-	int rc;
-
 	if (!copypaste_feat)
 		return -ENOTSUPP;
 
-	rc = vas_register_coproc_api(mod, cop_type, name, &vops_pseries);
-
-	return rc;
+	return vas_register_coproc_api(mod, cop_type, name, &vops_pseries);
 }
 EXPORT_SYMBOL_GPL(vas_register_api_pseries);