spi: cadence-qspi: Add support for Cadence Octal SPI controller

Cadence OSPI is similar to QSPI IP except that it supports Octal IO
(8 IO lines) flashes. Add support for Cadence OSPI IP with existing
driver using new compatible

Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Reviewed-by: Jagan Teki <jagan@amarulasolutions.com>
diff --git a/drivers/spi/cadence_qspi.c b/drivers/spi/cadence_qspi.c
index 619fff7..6374d39 100644
--- a/drivers/spi/cadence_qspi.c
+++ b/drivers/spi/cadence_qspi.c
@@ -6,6 +6,7 @@
 
 #include <common.h>
 #include <clk.h>
+#include <asm-generic/io.h>
 #include <dm.h>
 #include <fdtdec.h>
 #include <malloc.h>