tty: serial: samsung_tty: cast the interrupt's void *id just once

The interrupt handler routines and helpers are casting the 'void *'
pointer to 'struct exynos_uart_port *' all over the place.

There is no need for that, we can do the casting once and keep passing
the 'struct exynos_uart_port *', simplifying the code and saving a few
lines of code.

No functional changes.

Reviewed-by: Tudor Ambarus <tudor.ambarus@linaro.org>
Signed-off-by: André Draszik <andre.draszik@linaro.org>
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20240808-samsung-tty-cleanup-v3-2-494412f49f4b@linaro.org


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>