spi: spi-qcom-qspi: Ignore disabled interrupts' status in isr

During FIFO/DMA modes dynamic switching, only corresponding interrupts are
enabled. However its possible that FIFO related interrupt status registers
get set during DMA mode. For example WR_FIFO_EMPTY bit is set during DMA
TX.

Ignore such status bits so that they don't trip unwanted operations.

Suggested-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Vijaya Krishna Nivarthi <quic_vnivarth@quicinc.com>
Fixes: b5762d9 ("spi: spi-qcom-qspi: Add DMA mode support")
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Tested-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/1690285689-30233-2-git-send-email-quic_vnivarth@quicinc.com
Signed-off-by: Mark Brown <broonie@kernel.org>

Author: Vijaya Krishna Nivarthi

drivers/spi/spi-qcom-qspi.c

@@ -603,6 +603,9 @@ static irqreturn_t qcom_qspi_irq(int irq, void *dev_id)
 	int_status = readl(ctrl->base + MSTR_INT_STATUS);
 	writel(int_status, ctrl->base + MSTR_INT_STATUS);
 
+	/* Ignore disabled interrupts */
+	int_status &= readl(ctrl->base + MSTR_INT_EN);
+
 	/* PIO mode handling */
 	if (ctrl->xfer.dir == QSPI_WRITE) {
 		if (int_status & WR_FIFO_EMPTY)