arm: omap-common: add secure ROM signature verify index for AM33xx

On AM33xx devices the secure ROM uses a different call index for
signature verification, the function and arguments are the same.

Signed-off-by: Andrew F. Davis <afd@ti.com>
diff --git a/arch/arm/mach-omap2/sec-common.c b/arch/arm/mach-omap2/sec-common.c
index 246a239..c5a000a 100644
--- a/arch/arm/mach-omap2/sec-common.c
+++ b/arch/arm/mach-omap2/sec-common.c
@@ -21,7 +21,11 @@
 #include <spl.h>
 
 /* Index for signature verify ROM API */
+#ifdef CONFIG_AM33XX
+#define API_HAL_KM_VERIFYCERTIFICATESIGNATURE_INDEX	(0x0000000C)
+#else
 #define API_HAL_KM_VERIFYCERTIFICATESIGNATURE_INDEX	(0x0000000E)
+#endif
 
 static uint32_t secure_rom_call_args[5] __aligned(ARCH_DMA_MINALIGN);