e2fsck/revoke.c: sync changes from kernel

e2fsck/revoke.c: sync changes from kernel

Sync up the revoke.c specific changes from kernel commits 9bcf976cb8b8
("jbd2: remove unnecessary arguments of jbd2_journal_write_revoke_records"),
32ab671599a8 ("jbd2: factor out common descriptor block initialization"),
70fd76140a6c ("block,fs: use REQ_* flags directly"), cd9cb405e0b9
("jbd2: don't leak memory if setting up journal fails"), 8bdd5b60e027
("jbd2: remove NULL check before calling kmem_cache_destroy()"),
547b9ad698b4 ("jbd2: flush_descriptor(): Do not decrease buffer head's
ref count"), and fdc3ef882a5d ("jbd2: Reserve space for revoke descriptor
blocks").

Nearly all of the changes is in code under an #ifdef __KERNEL__.  The
changes that will actually affect e2fprogs compilation are trivial and
easy to hand verify.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>