Use the universally supported Vulkan "565" 16-bit texture format

Previously mistakenly used the BGR format instead of the RGB.

Probably won't make much of a difference for anything, but may affect #17881
if my theory about it is correct.

Also minor cleanups.

Core/HLE/sceDisplay.cpp

@@ -599,7 +599,7 @@ void __DisplayFlip(int cyclesLate) {
 	}
 
 	if (!FrameTimingThrottled()) {
-		NOTICE_LOG(SYSTEM, "Throttle: %d %d", (int)fastForwardSkipFlip, (int)postEffectRequiresFlip);
+		// NOTICE_LOG(SYSTEM, "Throttle: %d %d", (int)fastForwardSkipFlip, (int)postEffectRequiresFlip);
 	}
 
 	const bool fbDirty = gpu->FramebufferDirty();