Fix crash from plMouseDevice::HideCursor if it is called before cursor is created

Sources/Plasma/PubUtilLib/plInputCore/plInputDevice.cpp

@@ -481,7 +481,7 @@ void plMouseDevice::SetCursorY(hsScalar y)
 
 void plMouseDevice::HideCursor(hsBool override)
 {
-	if( fInstance->fCursor != nil )
+	if (fInstance && fInstance->fCursor)
 		fInstance->fCursor->SetVisible(false);
 
 	plMouseDevice::bCursorOverride = (override != 0);
@@ -499,10 +499,12 @@ void plMouseDevice::ShowCursor(hsBool override)
 	plMouseDevice::bCursorHidden = false;
 	plMouseDevice::bCursorOverride = false;
 	
-	if( fInstance->fCursor == nil )
+	if (fInstance) {
+		if (!fInstance->fCursor)
 			fInstance->CreateCursor(fInstance->fCursorID);
 		fInstance->fCursor->SetVisible(true);
 	}
+}
 
 void plMouseDevice::NewCursor(char* cursor)
 {