libtizonia: a port that does not support OMX_UseEGLImage should return OMX_ErrorNotImplemented

[juanrubio]

As suggested by @CapOM in Dev #344, a component needs to report OMX_ErrorNotImplemented when OMX_UseEGLImage is issued on a port that does not explicitely support this OpenMAX IL API.

The suggested approach is to use the tiz_eglimage_hook_t as a hint to libtizonia as to whether the port will support EGL images or not.

If the egl hook is not registered on a port, the call to OMX_UseEGLImage will return OMX_ErrorNotImplemented.