revised dp's for oh f4u1a and allen f4u1..gun fix

These are DP adjustments for the OH F4U1A and Allen's F4U1. Noticed in many models we don't actually have six .50 cal machine guns that actually fire, but four guns with two that are more a facade than anything. I noticed in DBOLTS F4U 1D this was remedied as in some P-47's that actually have...