regulator: arizona-ldo1: add missing #include

commit 2cce4be9e6 "regulator: arizona-ldo1: Add processing of init_data
from device tree" added a call to of_get_child_by_name() but
did not add an #include to the header file declaring that function.

I got a build error when doing randconfig testing on this, which
is fixed by this patch to include of.h.

drivers/regulator/arizona-ldo1.c:192:2: error: implicit declaration of function 'of_get_child_by_name' [-Werror=implicit-function-declaration]
drivers/regulator/arizona-ldo1.c:193:2: error: implicit declaration of function 'of_parse_phandle' [-Werror=implicit-function-declaration]
drivers/regulator/arizona-ldo1.c:213:2: error: implicit declaration of function 'of_node_put' [-Werror=implicit-function-declaration]

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

drivers/regulator/arizona-ldo1.c

@@ -16,6 +16,7 @@
 #include <linux/init.h>
 #include <linux/bitops.h>
 #include <linux/err.h>
+#include <linux/of.h>
 #include <linux/platform_device.h>
 #include <linux/regulator/driver.h>
 #include <linux/regulator/machine.h>