dmaengine: zxdma: Fix off-by-one for testing valid pchan request

The valid pchan range is 0 ~ d->dma_requests - 1.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Reviewed-by: Jun Nie <jun.nie@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
1 file changed