serial: core: introduce uart_port_tx_limited_flags()

commit 9bb43b9e upstream.

Analogue to uart_port_tx_flags() introduced in commit 3ee07964
("serial: core: introduce uart_port_tx_flags()"), add a _flags variant
for uart_port_tx_limited().

Fixes: d11cc8c3

 ("tty: serial: use uart_port_tx_limited()")
Cc: stable@vger.kernel.org
Signed-off-by: Jonas Gorski <jonas.gorski@gmail.com>
Signed-off-by: Doug Brown <doug@schmorgal.com>
Link: https://lore.kernel.org/r/20240606195632.173255-3-doug@schmorgal.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>