omap iommu: Fix Memory leak

The memory allocated for sgt structure is not freed on error
when sg_alloc_table is called in sgtable_alloc().

Signed-off-by: Satish Kumar <x0124230@ti.com>
Signed-off-by: Manjunatha GK <manjugk@ti.com>
Cc: Vimal Singh <vimal.newwork@gmail.com>
Signed-off-by: Hiroshi DOYU <Hiroshi.DOYU@nokia.com>
Signed-off-by: Tony Lindgen <tony@atomide.com>

arch/arm/plat-omap/iovmm.c

@@ -140,8 +140,10 @@ static struct sg_table *sgtable_alloc(const size_t bytes, u32 flags)
 		return ERR_PTR(-ENOMEM);
 
 	err = sg_alloc_table(sgt, nr_entries, GFP_KERNEL);
-	if (err)
+	if (err) {
+		kfree(sgt);
 		return ERR_PTR(err);
+	}
 
 	pr_debug("%s: sgt:%p(%d entries)\n", __func__, sgt, nr_entries);