platform/x86: ideapad-laptop: support Fn+R dual-function key

According to the manual, Fn+R adjusts the display refresh rate.
Map Fn+R to KEY_DISPLAYTOGGLE.
Signed-off-by: Gergo Koteles <soyer@irl.hu>
Link: https://lore.kernel.org/r/0cdbc0e6eb65e160384ae0ed152e7de3ded1d9d5.1707604991.git.soyer@irl.huReviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>

drivers/platform/x86/ideapad-laptop.c

@@ -1091,6 +1091,8 @@ static const struct key_entry ideapad_keymap[] = {
 	{ KE_KEY,	0x07 | IDEAPAD_WMI_KEY, { KEY_HELP } },
 	{ KE_KEY,	0x0e | IDEAPAD_WMI_KEY, { KEY_PICKUP_PHONE } },
 	{ KE_KEY,	0x0f | IDEAPAD_WMI_KEY, { KEY_HANGUP_PHONE } },
+	/* Refresh Rate Toggle (Fn+R) */
+	{ KE_KEY,	0x10 | IDEAPAD_WMI_KEY, { KEY_DISPLAYTOGGLE } },
 	/* Dark mode toggle */
 	{ KE_KEY,	0x13 | IDEAPAD_WMI_KEY, { KEY_PROG1 } },
 	/* Sound profile switch */