[LLDB][NFC][Reliability] Fix uninitialized variables from Coverity scan. Part 2

Improve LLDB reliability by fixing the following "uninitialized variables" static code inspection warnings from
scan.coverity.com:

1476275, 1274012, 1455035, 1364789, 1454282
1467483, 1406152, 1406255, 1454837, 1454416
1467446, 1462022, 1461909, 1420566, 1327228
1367767, 1431254, 1467299, 1312678, 1431780
1454731, 1490403

Differential Revision: https://reviews.llvm.org/D130528