hw/char/pl011: Extract pl011_write_txdata() from pl011_write()

When implementing FIFO, this code will become more complex.
Start by factoring it out to a new pl011_write_txdata() function.
No functional change intended.

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20240719181041.49545-7-philmd@linaro.org>
1 file changed