iommu/core: Convert iommu_found to iommu_present

With per-bus iommu_ops the iommu_found function needs to
work on a bus_type too. This patch adds a bus_type parameter
to that function and converts all call-places.
The function is also renamed to iommu_present because the
function now checks if an iommu is present for a given bus
and does not check for a global iommu anymore.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
diff --git a/include/linux/iommu.h b/include/linux/iommu.h
index c78d068..f56e559 100644
--- a/include/linux/iommu.h
+++ b/include/linux/iommu.h
@@ -56,7 +56,7 @@
 
 extern void register_iommu(struct iommu_ops *ops);
 extern int bus_set_iommu(struct bus_type *bus, struct iommu_ops *ops);
-extern bool iommu_found(void);
+extern bool iommu_present(struct bus_type *bus);
 extern struct iommu_domain *iommu_domain_alloc(struct bus_type *bus);
 extern void iommu_domain_free(struct iommu_domain *domain);
 extern int iommu_attach_device(struct iommu_domain *domain,
@@ -76,7 +76,7 @@
 
 struct iommu_ops {};
 
-static inline bool iommu_found(void)
+static inline bool iommu_present(struct bus_type *bus)
 {
 	return false;
 }