macintosh/ams/ams: Add header file macro definition

Add header file macro definition.

Signed-off-by: Li zeming <[e-mail]>
[mpe: Add endif comment]
Signed-off-by: Michael Ellerman <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]

drivers/macintosh/ams/ams.h

···
 /* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _AMS_H
+#define _AMS_H
+
 #include <linux/i2c.h>
 #include <linux/input.h>
 #include <linux/kthread.h>
···
 
 extern int ams_input_init(void);
 extern void ams_input_exit(void);
+
+#endif /* _AMS_H */