serial: qcom-geni: drop flip buffer WARN()

Drop the unnecessary WARN() in case the TTY buffers are ever full in
favour of a rate limited dev_err() which doesn't kill the machine when
panic_on_warn is set.

Reviewed-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
Link: https://lore.kernel.org/r/20241009145110.16847-8-johan+linaro@kernel.org


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