e2fsck: add kernel endian-ness conversion macros

e2fsck: add kernel endian-ness conversion macros

In order to make recovery.c identical with kernel, we need endianness
conversion macros (such as cpu_to_be32 and friends) defined in
e2fsprogs. This patch defines these macros and also fixes recovery.c
to use these. These macros are also needed for fast commit recovery
patches later in this series.

Signed-off-by: Harshad Shirwadkar <harshadshirwadkar@gmail.com>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>