fsck: Don't require tmp_obj_ file names are 14 bytes in length
Not all temporary file creation routines will ensure 14 bytes are used to generate the temporary file name. In C Git this may be true, but alternate implementations such as jgit are not always able to generate a temporary file name with a specific prefix and also ensure the file name length is 14 bytes long.
Since temporary files in a directory we are fsck'ing should be uncommon (as they are short lived only long enough for an active writer to finish writing the file and rename it) we shouldn't see these show up very often. Always using a prefixcmp() call and ignoring the length opens up room for other implementations to use different name generation schemes.
Signed-off-by: Shawn O. Pearce <email@example.com> Signed-off-by: Junio C Hamano <firstname.lastname@example.org>