verify_pack: do not ignore return value of verification function
verify_pack: do not ignore return value of verification function

In verify_pack, a caller-supplied verification function is called.
The function returns an int.  If that return value is non-zero,
verify_pack should fail.

The only caller of verify_pack is in builtin/fsck.c, whose verify_fn
returns a meaningful error code (which was then ignored).  Now, fsck
might return a different error code (with more detail).  This would
happen in the unlikely event that a commit or tree that is a valid git
object but not a valid instance of its type gets into a pack.

Signed-off-by: David Turner <a13b1135e6f2f8530e85bc2896cd5ed89a6ed863@twopensource.com>
Signed-off-by: Jeff King <696e3fbcf235d40b6ea1ebd61c87cbea79d444e7@peff.net>

destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git