There is one signedness issue in tdb which prevents traverses of TDB records over...

There is one signedness issue in tdb which prevents traverses of TDB records over the 2G offset on systems which support 64 bit file offsets. This fixes that case.

On systems with 32 bit offsets, expansion and fcntl locking on these records
will fail anyway.  SAMBA already does '#define _FILE_OFFSET_BITS 64' in
config.h (on my 32-bit x86 Linux system at least) to get 64 bit file offsets.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
(cherry picked from samba commit 252f7da702fd0409f7bfff05ef594911ededa32f)

Signed-off-by: Stefan Metzmacher <metze@samba.org>