Fix for a valgrind warning due to a jump on a uninitialized
variable. The problem was that the sql profile preparation
function wasn't being called for all possible code paths
of query execution.

The solution is to ensure that query profiling is always
started before dispatch_command function is called and to
explicitly call the profile preparation function on bootstrap.



sql/sql_parse.cc:
  Finish query profiling properly when executing bootstrap commands.
  Add query profiling to execute_init_command as it calls dispatch_command.