iommu/amd: fix type bug in flush code

write_file_bool() modifies 32 bits of data, so "amd_iommu_unmap_flush"
needs to be 32 bits as well or we'll corrupt memory.  Fortunately it
looks like the data is aligned with a gap after the declaration so this
is harmless in production.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>

drivers/iommu/amd_iommu.c

@@ -404,7 +404,7 @@ static void amd_iommu_stats_init(void)
 		return;
 
 	de_fflush  = debugfs_create_bool("fullflush", 0444, stats_dir,
-					 (u32 *)&amd_iommu_unmap_flush);
+					 &amd_iommu_unmap_flush);
 
 	amd_iommu_stats_add(&compl_wait);
 	amd_iommu_stats_add(&cnt_map_single);

drivers/iommu/amd_iommu_init.c

@@ -129,7 +129,7 @@ u16 amd_iommu_last_bdf;			/* largest PCI device id we have
 					   to handle */
 LIST_HEAD(amd_iommu_unity_map);		/* a list of required unity mappings
 					   we find in ACPI */
-bool amd_iommu_unmap_flush;		/* if true, flush on every unmap */
+u32 amd_iommu_unmap_flush;		/* if true, flush on every unmap */
 
 LIST_HEAD(amd_iommu_list);		/* list of all AMD IOMMUs in the
 					   system */

drivers/iommu/amd_iommu_types.h

@@ -652,7 +652,7 @@ extern unsigned long *amd_iommu_pd_alloc_bitmap;
  * If true, the addresses will be flushed on unmap time, not when
  * they are reused
  */
-extern bool amd_iommu_unmap_flush;
+extern u32 amd_iommu_unmap_flush;
 
 /* Smallest number of PASIDs supported by any IOMMU in the system */
 extern u32 amd_iommu_max_pasids;