ext4: Convert bg_inode_bitmap and bg_inode_table

Convert bg_inode_bitmap and bg_inode_table to bg_inode_bitmap_lo
and bg_inode_table_lo.  This helps in finding BUGs due to
direct partial access of these split 64 bit values

Also fix one direct partial access

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
diff --git a/include/linux/ext4_fs.h b/include/linux/ext4_fs.h
index 1dab984..f5d57c7 100644
--- a/include/linux/ext4_fs.h
+++ b/include/linux/ext4_fs.h
@@ -106,8 +106,8 @@
 struct ext4_group_desc
 {
 	__le32	bg_block_bitmap_lo;	/* Blocks bitmap block */
-	__le32	bg_inode_bitmap;	/* Inodes bitmap block */
-	__le32	bg_inode_table;		/* Inodes table block */
+	__le32	bg_inode_bitmap_lo;	/* Inodes bitmap block */
+	__le32	bg_inode_table_lo;	/* Inodes table block */
 	__le16	bg_free_blocks_count;	/* Free blocks count */
 	__le16	bg_free_inodes_count;	/* Free inodes count */
 	__le16	bg_used_dirs_count;	/* Directories count */