serial: liteuart: Correct error rollback

Goto to the correct rollback label instead of directly returning.

Fixes: 5602cf99

 ("serial: liteuart: add IRQ support for the RX path")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Gabriel Somlo <gsomlo@gmail.com>
Link: https://lore.kernel.org/r/20230123173857.40695-3-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>