Investigate and add main entry point for iOS when linking applications

!bitcode {
        # By marking qt_registerPlatformPlugin as undefined, we ensure that
        # the plugin.o translation unit is considered for inclusion in
        # the final binary, which in turn ensures that the plugin's
        # static initializer is included and run.
        QMAKE_LFLAGS += -u _qt_registerPlatformPlugin
    }

    !no_main_wrapper {
        # The LC_MAIN load command available in iOS 6.0 and above allows dyld to
        # directly call the entrypoint instead of going through _start in crt.o.
        # Passing -e to the linker changes the entrypoint from _main to our custom
        # wrapper that calls UIApplicationMain and dispatches back to main() once
        # the application has started up and is ready to initialize QApplication.
        QMAKE_LFLAGS += -Wl,-e,_qt_main_wrapper
    }