param: fix return value handling in param_set_*

In STANDARD_PARAM_DEF, param_set_* handles the case in which strtolfn
returns -EINVAL but it may return -ERANGE. If it returns -ERANGE,
param_set_* may set uninitialized value to the paramerter. We should handle
both cases.

The one of the cases in which strtolfn() returns -ERANGE is following:

 *Type of module parameter is long
 *Set the parameter more than LONG_MAX

Signed-off-by: Satoru Moriya <satoru.moriya@hds.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

kernel/params.c

@@ -225,8 +225,8 @@ int parse_args(const char *name,
 		int ret;						\
 									\
 		ret = strtolfn(val, 0, &l);				\
-		if (ret == -EINVAL || ((type)l != l))			\
-			return -EINVAL;					\
+		if (ret < 0 || ((type)l != l))				\
+			return ret < 0 ? ret : -EINVAL;			\
 		*((type *)kp->arg) = l;					\
 		return 0;						\
 	}								\