Fix animation glitch caused by knockdown

If the player was knocked down while having no weapon, spell nor fists ready, the animation state would incorrectly shift to "weapon equipped" even though no weapon is equipped.

apps/openmw/mwmechanics/character.cpp

@@ -1072,7 +1072,8 @@ bool CharacterController::updateWeaponState()
         }
         else if (mHitState == CharState_KnockDown)
         {
-            mUpperBodyState = UpperCharState_WeapEquiped;
+            if (mUpperBodyState > UpperCharState_WeapEquiped)
+                mUpperBodyState = UpperCharState_WeapEquiped;
             mAnimation->disable(mCurrentWeapon);
         }
     }