regulator: Add rdev_crit() macro

No actual users but provide the macro so there's less surprise when it's
not there.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>

drivers/regulator/core.c

@@ -34,6 +34,8 @@
 
 #include "dummy.h"
 
+#define rdev_crit(rdev, fmt, ...)					\
+	pr_crit("%s: " fmt, rdev_get_name(rdev), ##__VA_ARGS__)
 #define rdev_err(rdev, fmt, ...)					\
 	pr_err("%s: " fmt, rdev_get_name(rdev), ##__VA_ARGS__)
 #define rdev_warn(rdev, fmt, ...)					\