Updated cppcheck suppressions; fixed some warnings
Updated some suppressions:
- removed some that are fixed by 1.82
- for some useful warnings that were totally suppressed, now only suppress them in files where actual errors currently exist, thus allowing us to stop new such ones being added
Fixed some warnings:
- a few invalidPointerCast warnings
- branch where ‘node_name’ string is used uninitialized
- dead variable, dead store
- removed unused ivar