Fix crash on rapid reconnect.

[LosawI]

I noticed that when unplugging and replugging the camera, and giving the autorization too fast, it made the application crash.
After debugging, I found that the vm->DetachCurrentThread() was called sometimes on a wrong thread, and I came up with this fix in the UVCStatusCallback.cpp on the uvc_status_callback method. I don't know if it is how it should be done, but it worked for me :

void UVCStatusCallback::uvc_status_callback(uvc_status_class status_class, int event, int selector, uvc_status_attribute status_attribute, void *data, size_t data_len, void *user_ptr) {

	UVCStatusCallback *statusCallback = reinterpret_cast<UVCStatusCallback *>(user_ptr);
	if (!statusCallback) return;

	JavaVM *vm = getVM();
	if (!vm) return;

	JNIEnv *env = nullptr;
	bool needsDetach = false; 

	int getEnvStat = vm->GetEnv(reinterpret_cast<void **>(&env), JNI_VERSION_1_6);

	if (getEnvStat == JNI_EDETACHED) {
		if (vm->AttachCurrentThread(&env, nullptr) != 0) {
			LOGE("Failed to attach current thread");
			return;
		}
		needsDetach = true;
	} else if (getEnvStat == JNI_EVERSION) {
		LOGE("GetEnv: version not supported");
		return;
	}

	statusCallback->notifyStatusCallback(env, status_class, event, selector, status_attribute, data, data_len);

	if (needsDetach) {
		vm->DetachCurrentThread();
	}
}