Input: twl4030-pwrbutton - add missing of.h include

The driver is using of_match_ptr() and therefore needs to include
of.h header.
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20220927052217.2784593-1-dmitry.torokhov@gmail.comSigned-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

drivers/input/misc/twl4030-pwrbutton.c

@@ -26,6 +26,7 @@
 #include <linux/errno.h>
 #include <linux/input.h>
 #include <linux/interrupt.h>
+#include <linux/of.h>
 #include <linux/platform_device.h>
 #include <linux/mfd/twl.h>