leds: TI_LMU_COMMON: select REGMAP instead of depending on it

REGMAP is a hidden (not user visible) symbol. Users cannot set it
directly thru "make *config", so drivers should select it instead of
depending on it if they need it.

Consistently using "select" or "depends on" can also help reduce
Kconfig circular dependency issues.

Therefore, change the use of "depends on REGMAP" to "select REGMAP".

Fixes: 3fce8e1e ("leds: TI LMU: Add common code for TI LMU devices")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Lee Jones <lee@kernel.org>
Link: https://lore.kernel.org/r/20230226053953.4681-5-rdunlap@infradead.org

drivers/leds/Kconfig

@@ -795,7 +795,7 @@ config LEDS_SPI_BYTE
 config LEDS_TI_LMU_COMMON
 	tristate "LED driver for TI LMU"
 	depends on LEDS_CLASS
-	depends on REGMAP
+	select REGMAP
 	help
 	  Say Y to enable the LED driver for TI LMU devices.
 	  This supports common features between the TI LM3532, LM3631, LM3632,