ext4: functions should not be declared extern

The function declarations in ext4.h are already marked extern, so it's
not necessary to do so in the .c files.

This quiets the sparse noise:

warning: function 'ext4_flush_completed_IO' with external linkage has definition
warning: function 'ext4_init_inode_table' with external linkage has definition

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
diff --git a/fs/ext4/fsync.c b/fs/ext4/fsync.c
index 036f78f..c942924 100644
--- a/fs/ext4/fsync.c
+++ b/fs/ext4/fsync.c
@@ -75,7 +75,7 @@
  * to written.
  * The function return the number of pending IOs on success.
  */
-extern int ext4_flush_completed_IO(struct inode *inode)
+int ext4_flush_completed_IO(struct inode *inode)
 {
 	ext4_io_end_t *io;
 	struct ext4_inode_info *ei = EXT4_I(inode);