vboot_ui_menu: Use volume down short press at recovery menu screen

Fix the typo made in
https://chromium-review.googlesource.com/c/chromiumos/platform/vboot_reference/+/757123
for usage of volume down button at recovery menu screen. It should be
short press instead of long press.

BUG=b:64992445,b:65013794
BRANCH=None
TEST=Verified that volume down short press works as expected on
recovery menu.

Change-Id: Ia9a172439ac3bbd1ea395778e83a95c988816e01
Signed-off-by: Furquan Shaikh <furquan@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/767059
Reviewed-by: Shelley Chen <shchen@chromium.org>
diff --git a/firmware/lib/vboot_ui_menu.c b/firmware/lib/vboot_ui_menu.c
index 9199306..9c7c5b8 100644
--- a/firmware/lib/vboot_ui_menu.c
+++ b/firmware/lib/vboot_ui_menu.c
@@ -1126,7 +1126,7 @@
 			case VB_KEY_UP:
 			case VB_KEY_DOWN:
 			case VB_BUTTON_VOL_UP_SHORT_PRESS:
-			case VB_BUTTON_VOL_DOWN_LONG_PRESS:
+			case VB_BUTTON_VOL_DOWN_SHORT_PRESS:
 				/* User cannot use keyboard to enable dev mode.
 				 * They need to use the volume buttons from a
 				 * trusted source to navigate to the disable os