iOS: Fix always-true condition in the gsEvent key decoder

"else if (GSEVENT_TYPE_KEYDOWN)" tests a constant, so every gsEvent that wasn't
a key up - modifier events (type 12) in particular - was delivered to NativeKey
as a key down.

Co-Authored-By: Claude Opus 5 <[email protected]>
Claude-Session: https://claude.ai/code/session_01JZk5y4Fzw811WJoNWZb8Sc

ios/PPSSPPUIApplication.mm

@@ -81,7 +81,7 @@
 		key.keyCode = getSmartKeyboardMap((int)eventScanCode);
 		key.deviceId = DEVICE_ID_KEYBOARD;
 		NativeKey(key);
-	} else if (GSEVENT_TYPE_KEYDOWN) {
+	} else if (eventType == GSEVENT_TYPE_KEYDOWN) {
 		struct KeyInput key;
 		key.flags = KeyInputFlags::DOWN;
 		key.keyCode = getSmartKeyboardMap((int)eventScanCode);