xilinx_spips: Correct the number of dummy cycles for the FAST_READ_4 cmd

Correct the number of dummy cycles required by the FAST_READ_4 command (to
be eight, one dummy byte).

Fixes: ef06ca39 ("xilinx_spips: Add support for RX discard and RX drain")
Suggested-by: NCédric Le Goater <clg@kaod.org>
Signed-off-by: NFrancisco Iglesias <frasse.iglesias@gmail.com>
Reviewed-by: NEdgar E. Iglesias <edgar.iglesias@xilinx.com>
Message-id: 20200218113350.6090-1-frasse.iglesias@gmail.com
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

hw/ssi/xilinx_spips.c

@@ -576,11 +576,11 @@ static int xilinx_spips_num_dummies(XilinxQSPIPS *qs, uint8_t command)
     case FAST_READ:
     case DOR:
     case QOR:
+    case FAST_READ_4:
     case DOR_4:
     case QOR_4:
         return 1;
     case DIOR:
-    case FAST_READ_4:
     case DIOR_4:
         return 2;
     case QIOR: