Delete special-case "out-of-range" handling for bools, and just use the normal

codepath plus the new "minimum / maximum value of type" diagnostic to get the
same effect.

Move the warning for an in-range but tautological comparison of a constant (0
or 1) against a bool out of -Wtautological-constant-out-of-range-compare into
the more-appropriate -Wtautological-constant-compare.

llvm-svn: 319942