ext2fs: Remove redundant brelse() after r294954

Coccinelle:

@ rule1 @
identifier error;
@@
...
int error;
...

@ rule2 depends on rule1 @
identifier rule1.error;
identifier bp;
@@

__error =
(
bread

bread_gb

breadn

breadn_flags
)
(..., &bp);
if (
(
error

__error != 0
)
) {
...

• brelse(__bp); ... }

No functional change.