asus-laptop: Add key found on Asus F3M

Asus F3M has two keys labeled with an icon of a touchpad. The first,
reported as 0x6B is next to the power key and the second, reported as
0x6A, is F9 combined with Fn button. When I was pressing the latter, I was
getting "Unknown key 6a pressed" message before applying this patch.

Asus F3M does not support WMI so the commit does not update key mappings
in the asus-nb-wmi.c file.

I have not tested this mapping on any other Asus laptop.
Signed-off-by: Łukasz Stelmach <stlman@poczta.fm>
Signed-off-by: Darren Hart <dvhart@linux.intel.com>

drivers/platform/x86/asus-laptop.c

@@ -332,6 +332,7 @@ static const struct key_entry asus_keymap[] = {
 	{KE_KEY, 0x65, { KEY_SWITCHVIDEOMODE } }, /* SDSP LCD + TV */
 	{KE_KEY, 0x66, { KEY_SWITCHVIDEOMODE } }, /* SDSP CRT + TV */
 	{KE_KEY, 0x67, { KEY_SWITCHVIDEOMODE } }, /* SDSP LCD + CRT + TV */
+	{KE_KEY, 0x6A, { KEY_TOUCHPAD_TOGGLE } }, /* Lock Touchpad Fn + F9 */
 	{KE_KEY, 0x6B, { KEY_TOUCHPAD_TOGGLE } }, /* Lock Touchpad */
 	{KE_KEY, 0x6C, { KEY_SLEEP } }, /* Suspend */
 	{KE_KEY, 0x6D, { KEY_SLEEP } }, /* Hibernate */