fallocate() may potentially instantiate blocks past EOF, depending
on the flags used when it is called.

e2fsck currently has a test for blocks past i_size, and it
sometimes trips up - noticeably on xfstests 013 which runs fsstress.

This patch from Jiayang does fix it up - it (along with
e2fsprogs updates and other patches recently from Aneesh) has
survived many fsstress runs in a row.
Signed-off-by: NEric Sandeen <sandeen@redhat.com>
Signed-off-by: NJiaying Zhang <jiayingz@google.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>