fix(st-regulator): enclose macro parameters in parentheses

This corrects MISRA C2012-20.7:
Expressions resulting from the expansion of macro parameters shall be
enclosed in parentheses.

Signed-off-by: Yann Gautier <yann.gautier@st.com>
Change-Id: I9989a5aaacf17f6f7a65381c8d41f21a35f6ddd9

drivers/st/regulator/regulator_core.c

@@ -22,11 +22,11 @@ CASSERT(PLAT_NB_RDEVS >= 1U, plat_nb_rdevs_must_be_higher);
 static struct rdev rdev_array[PLAT_NB_RDEVS];
 
 #define for_each_rdev(rdev) \
-	for (rdev = rdev_array; rdev <= &rdev_array[PLAT_NB_RDEVS - 1U]; rdev++)
+	for ((rdev) = rdev_array; (rdev) <= &rdev_array[PLAT_NB_RDEVS - 1U]; (rdev)++)
 
 #define for_each_registered_rdev(rdev) \
-	for (rdev = rdev_array; \
-	     (rdev <= &rdev_array[PLAT_NB_RDEVS - 1U]) && (rdev->desc != NULL); rdev++)
+	for ((rdev) = rdev_array; \
+	     ((rdev) <= &rdev_array[PLAT_NB_RDEVS - 1U]) && ((rdev)->desc != NULL); (rdev)++)
 
 static void lock_driver(const struct rdev *rdev)
 {