DERBY-6183 rlliso2multi and rlliso3multi failing with [WARNING 01004: Data truncation]

backported change #1469445 from trunk to 10.10 branch.

Removed casts from lock_table2 view, which was only used in a few
places. I was not able to reproduce, but assumption is that a
system background lock when running full suite sometimes triggered
a problem with the cast. 



git-svn-id: https://svn.apache.org/repos/asf/db/derby/code/branches/10.10@1469624 13f79535-47bb-0310-9956-ffa450edef68