Commander: add comment in COM_RC_OVERRIDE that it's always enabled in Descend mdoe

Signed-off-by: Silvan Fuhrer <silvan@auterion.com>

src/modules/commander/commander_params.c

@@ -645,6 +645,9 @@ PARAM_DEFINE_INT32(COM_REARM_GRACE, 1);
  * their center position immediately gives control back to the pilot by switching to Position mode.
  * Note: Only has an effect on multicopters, and VTOLs in multicopter mode.
  *
+ * This parameter is not considered in case of a GPS failure (Descend flight mode), where stick
+ * override is always enabled.
+ *
  * @min 0
  * @max 7
  * @bit 0 Enable override during auto modes (except for in critical battery reaction)