HID: hid-alps: Correct struct misnaming

Fixes the following W=1 kernel build warning(s):

 drivers/hid/hid-alps.c:113: warning: expecting prototype for struct u1_data. Prototype was for struct alps_dev instead

Cc: Jiri Kosina <jikos@kernel.org>
Cc: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Cc: Henrik Rydberg <rydberg@bitmath.org>
Cc: Masaki Ota <masaki.ota@jp.alps.com>
Cc: linux-input@vger.kernel.org
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>

drivers/hid/hid-alps.c

@@ -74,7 +74,7 @@ enum dev_num {
 	UNKNOWN,
 };
 /**
- * struct u1_data
+ * struct alps_dev
  *
  * @input: pointer to the kernel input device
  * @input2: pointer to the kernel input2 device