e2fsck: remove EXT4_EOFBLOCKS_FL flag handling

e2fsck: remove EXT4_EOFBLOCKS_FL flag handling

We've decided to remove EOFBLOCKS_FL from the ext4 file system entirely,
because it is not actually very useful and it is causing more problems
than it solves. We're going to remove it from e2fsprogs first and then
after the new e2fsprogs version is common enough we can remove the
kernel part as well.

This commit changes e2fsck to not check for EOFBLOCKS_FL. Instead we
simply search for initialized extents past the i_size as this should not
happen. Uninitialized extents can be past the i_size as we can do
fallocate with KEEP_SIZE flag.

Also remove the EXT4_EOFBLOCKS_FL from lib/ext2fs/ext2_fs.h since it is
no longer needed.

Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>