iommu/shmobile: Depend on ARCH_SHMOBILE

Commit 78a2e12f ("iommu: shmobile: Enable driver compilation with
COMPILE_TEST") added an optional dependency on SH_MOBILE. But that
Kconfig symbol doesn't exist. It seems ARCH_SHMOBILE was intended. Use
that.
Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Joerg Roedel <joro@8bytes.org>

drivers/iommu/Kconfig

@@ -207,7 +207,7 @@ config SHMOBILE_IOMMU
 	bool "IOMMU for Renesas IPMMU/IPMMUI"
 	default n
 	depends on ARM
-	depends on SH_MOBILE || COMPILE_TEST
+	depends on ARCH_SHMOBILE || COMPILE_TEST
 	select IOMMU_API
 	select ARM_DMA_USE_IOMMU
 	select SHMOBILE_IPMMU