serial: liteuart: fix minor-number leak on probe errors

serial: liteuart: fix minor-number leak on probe errors

BugLink: https://bugs.launchpad.net/bugs/1953731
commit dd5e90b16cca8a697cbe17b72e2a5f49291cabb2 upstream.

Make sure to release the allocated minor number before returning on
probe errors.

Fixes: 1da81e5562fa ("drivers/tty/serial: add LiteUART driver")
Cc: stable@vger.kernel.org      # 5.11
Cc: Filip Kokosinski <fkokosinski@antmicro.com>
Cc: Mateusz Holenko <mholenko@antmicro.com>
Reviewed-by: Stafford Horne <shorne@gmail.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20211117100512.5058-3-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Paolo Pisati <paolo.pisati@canonical.com>