dt-bindings: input: adopt Linux gpio-keys binding constants

Sync the gpio-keys input bindings from linux 5.7-rc1.

Signed-off-by: Peter Robinson <pbrobinson@gmail.com>

include/dt-bindings/input/gpio-keys.h

@@ -0,0 +1,13 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * This header provides constants for gpio keys bindings.
+ */
+
+#ifndef _DT_BINDINGS_GPIO_KEYS_H
+#define _DT_BINDINGS_GPIO_KEYS_H
+
+#define EV_ACT_ANY		0x00	/* asserted or deasserted */
+#define EV_ACT_ASSERTED		0x01	/* asserted */
+#define EV_ACT_DEASSERTED	0x02	/* deasserted */
+
+#endif /* _DT_BINDINGS_GPIO_KEYS_H */