serial: qcom_geni_serial: Always use 4 bytes per TX FIFO word

The geni serial driver had a rule that we'd only use 1 byte per FIFO
word for the TX FIFO if we were being used for the serial console.
This is ugly and a bit of a pain.  It's not too hard to fix, so fix
it.

Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Evan Green <evgreen@chromium.org>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20200626125844.2.Iabd56347670b9e4e916422773aba5b27943d19ee@changeid


Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>