regulator: da9121: include linux/gpio/consumer.h

When CONFIG_GPIOLIB is disabled, the declarations from linux/gpio/consumer.h
are not visible:

drivers/regulator/da9121-regulator.c:371:14: error: implicit declaration of function 'fwnode_gpiod_get_index' [-Werror,-Wimplicit-function-declaration]
        ena_gpiod = fwnode_gpiod_get_index(of_fwnode_handle(np), "enable", 0,
                    ^
drivers/regulator/da9121-regulator.c:372:7: error: use of undeclared identifier 'GPIOD_OUT_HIGH'
                                                GPIOD_OUT_HIGH |
                                                ^
drivers/regulator/da9121-regulator.c:373:7: error: use of undeclared identifier 'GPIOD_FLAGS_BIT_NONEXCLUSIVE'
                                                GPIOD_FLAGS_BIT_NONEXCLUSIVE,

Include this explicitly to help compile testing.

Fixes: 46c413d5 ("regulator: da9121: Add support for device variants via devicetree")
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/20201204165229.3754763-1-arnd@kernel.orgSigned-off-by: NMark Brown <broonie@kernel.org>

drivers/regulator/da9121-regulator.c

@@ -15,6 +15,7 @@
 
 #include <linux/of_device.h>
 #include <linux/of_gpio.h>
+#include <linux/gpio/consumer.h>
 #include <linux/regulator/of_regulator.h>
 #include <linux/regulator/machine.h>
 #include <linux/regulator/driver.h>