iio: magnetometer: fix if () scoped_guard() formatting

Add mising braces after an if condition that contains scoped_guard().

This style is both preferred and necessary here, to fix warning after
scoped_guard() change in commit fcc22ac ("cleanup: Adjust
scoped_guard() macros to avoid potential warning") to have if-else inside
of the macro. Current (no braces) use in af8133j_set_scale() yields
the following warnings:
af8133j.c:315:12: warning: suggest explicit braces to avoid ambiguous 'else' [-Wdangling-else]
af8133j.c:316:3: warning: add explicit braces to avoid dangling else [-Wdangling-else]

Fixes: fcc22ac ("cleanup: Adjust scoped_guard() macros to avoid potential warning")
Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/
Reported-by: kernel test robot <[email protected]>
Signed-off-by: Stephen Rothwell <[email protected]>
Signed-off-by: Przemek Kitszel <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Acked-by: Jonathan Cameron <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

Author: sfrothwell

drivers/iio/magnetometer/af8133j.c

@@ -312,10 +312,11 @@ static int af8133j_set_scale(struct af8133j_data *data,
 	 * When suspended, just store the new range to data->range to be
 	 * applied later during power up.
 	 */
-	if (!pm_runtime_status_suspended(dev))
+	if (!pm_runtime_status_suspended(dev)) {
 		scoped_guard(mutex, &data->mutex)
 			ret = regmap_write(data->regmap,
 					   AF8133J_REG_RANGE, range);
+	}
 
 	pm_runtime_enable(dev);