mtd: m25p80: add support of octal mode I/O transfer

Add support for octal mode I/O data transfer based on the controller (spi)
mode.
Assign hw-capability mask bits for octal transfer.

Signed-off-by: Yogesh Narayan Gaur <yogeshnarayan.gaur@nxp.com>
Reviewed-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Signed-off-by: Boris Brezillon <bbrezillon@kernel.org>

drivers/mtd/devices/m25p80.c

@@ -195,7 +195,14 @@ static int m25p_probe(struct spi_mem *spimem)
 	spi_mem_set_drvdata(spimem, flash);
 	flash->spimem = spimem;
 
-	if (spi->mode & SPI_RX_QUAD) {
+	if (spi->mode & SPI_RX_OCTAL) {
+		hwcaps.mask |= SNOR_HWCAPS_READ_1_1_8;
+
+		if (spi->mode & SPI_TX_OCTAL)
+			hwcaps.mask |= (SNOR_HWCAPS_READ_1_8_8 |
+					SNOR_HWCAPS_PP_1_1_8 |
+					SNOR_HWCAPS_PP_1_8_8);
+	} else if (spi->mode & SPI_RX_QUAD) {
 		hwcaps.mask |= SNOR_HWCAPS_READ_1_1_4;
 
 		if (spi->mode & SPI_TX_QUAD)