ext4: make local functions static

I have been running make namespacecheck to look for unneeded globals, and
found these in ext4.

Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

diff --cc fs/ext4/balloc.c
Simple merge

diff --cc fs/ext4/ext4.h
Simple merge

diff --cc fs/ext4/ext4_jbd2.c
Simple merge

diff --cc fs/ext4/ext4_jbd2.h
Simple merge

diff --cc fs/ext4/file.c
Simple merge

diff --cc fs/ext4/inline.c
Simple merge

diff --cc fs/ext4/inode.c
Simple merge

diff --cc fs/ext4/mmp.c
Simple merge

diff --cc fs/ext4/super.c
Simple merge