New warnfixes (#2254)

* Fix clang warnings

* Remove vim tab guides

* initialize variables

* 'strncpy' output truncated before terminating nul copying as many bytes from a string as its length

* Fix ISO C++17 does not allow 'register' storage class specifier for outdated bison

* chars are unsigned on ARM, having  if (ival < 0) always false

* chars are unsigned by default on ARM and comparison with -1 if always true

versioning/BRM/extentmap.cpp

@@ -5953,4 +5953,3 @@ template int ExtentMap::getMaxMin<int64_t>(const LBID_t lbidRange, int64_t& max,
                                            int32_t& seqNum);
 
 }  // namespace BRM
-// vim:ts=4 sw=4: