[STATS] separate noTotal bit flag from onlyInMaster and noUnits

This change logically separates the stats_flags_e::noTotal bit flag from the
stats_flags_e::onlyInMaster and stats_flags_e::noUnits bit flags. If no
TOTAL_foo output is wanted for a particular statistic, the flag must be
explicitly included in that statistic's flags.

Differential Revision: http://reviews.llvm.org/D18198

llvm-svn: 263954