Tweak google support

Author: ReallySmallSoftware

src/ios/FirebaseUIAuthPlugin.m

@@ -54,7 +54,7 @@ - (void)createProviderList:(NSDictionary *)options {
 
         for (NSString *provider in providers) {
 
-            Boolean google = [iOSDisable isEqualToNumber:[NSNumber numberWithBool:YES]];
+            Boolean google = ![iOSDisable isEqualToNumber:[NSNumber numberWithBool:YES]];
 
             if (@available(iOS 11.0, *)) {
                 google = true;