spi: spi-geni-qcom: Remove confusing comment about setting the watermark

The comment in setup_fifo_xfer() about setting the watermark wasn't
quite proper grammar and also stopped making sense around commit
6d66507d ("spi: spi-geni-qcom: Don't wait to start 1st transfer if
transmitting"). After that commit we actually start the transfer
_before_ the watermark interrupt comes.

I don't think the comment really has any value anymore. We've already
got a comment when we grab the spinlock saying that our interrupt can
come any time as a result of the things in the locked section. Let's
just remove it.
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Vinod Koul <vkoul@kernel.org>
Link: https://lore.kernel.org/r/20210712085010.1.Ie3bb9f9d30d6475bb75251d32635194c1c72b9ee@changeidSigned-off-by: Mark Brown <broonie@kernel.org>

drivers/spi/spi-geni-qcom.c

@@ -549,12 +549,6 @@ static void setup_fifo_xfer(struct spi_transfer *xfer,
 	 */
 	spin_lock_irq(&mas->lock);
 	geni_se_setup_m_cmd(se, m_cmd, FRAGMENTATION);
-
-	/*
-	 * TX_WATERMARK_REG should be set after SPI configuration and
-	 * setting up GENI SE engine, as driver starts data transfer
-	 * for the watermark interrupt.
-	 */
 	if (m_cmd & SPI_TX_ONLY) {
 		if (geni_spi_handle_tx(mas))
 			writel(mas->tx_wm, se->base + SE_GENI_TX_WATERMARK_REG);