Branch condition evaluates to a garbage value

[QiAnXinCodeSafe]

https://github.com/intel/libyami/blob/90ac9995763ad569157b3a216da88e090720ed70/encoder/vaapiencoder_base.cpp#L686

'isEmpty' declared without an initial value https://github.com/intel/libyami/blob/90ac9995763ad569157b3a216da88e090720ed70/encoder/vaapiencoder_base.cpp#L681

Calling 'checkEmpty()' in line 685, and the checkEmpty() defined in line 642. Entered call from 'checkEmpty()', returning without writing to '*outEmpty'

https://github.com/intel/libyami/blob/90ac9995763ad569157b3a216da88e090720ed70/encoder/vaapiencoder_base.cpp#L647