Stop overanxious htonl in vldb_check -fix

Stop overanxious htonl in vldb_check -fix

vldb_check -fix is corrupting the server entries (Number, Partition,
Flags).  This is because it is doing a htonl on what is a char field.
The read code already has a comment "make sure not to ntohl these,
as they're chars, not ints".

This change strips the corresponding htonl from writeheader (and puts
in a similar comment).

Change-Id: I5902be0f1e928521bfcb5ec66edd227c08ea2bdc
Reviewed-on: http://gerrit.openafs.org/1964
Reviewed-by: Derrick Brashear <shadow@dementia.org>
Tested-by: Derrick Brashear <shadow@dementia.org>