Update to more CodeGen tests to use CHECK-LABEL for labels corresponding to function definitions for more informative error  messages. No functionality change.

All changes were made by the following bash script:

  find test/CodeGen -name "*.ll" | \
  while read NAME; do
    echo "$NAME"
    grep -q "^; *RUN: *llc.*debug" $NAME && continue
    grep -q "^; *RUN:.*llvm-objdump" $NAME && continue
    grep -q "^; *RUN: *opt.*" $NAME && continue
    TEMP=`mktemp -t temp`
    cp $NAME $TEMP
    sed -n "s/^define [^@]*@\([A-Za-z0-9_]*\)(.*$/\1/p" < $NAME | \
    while read FUNC; do
      sed -i '' "s/;\([A-Za-z0-9_-]*\)\([A-Za-z0-9_-]*\):\( *\)$FUNC[:]* *\$/;\1\2-LABEL:\3$FUNC:/g" $TEMP
    done
    sed -i '' "s/;\(.*\)-LABEL-LABEL:/;\1-LABEL:/" $TEMP
    sed -i '' "s/;\(.*\)-NEXT-LABEL:/;\1-NEXT:/" $TEMP
    sed -i '' "s/;\(.*\)-NOT-LABEL:/;\1-NOT:/" $TEMP
    sed -i '' "s/;\(.*\)-DAG-LABEL:/;\1-DAG:/" $TEMP
    mv $TEMP $NAME
  done

This script catches a superset of the cases caught by the script associated with commit r186280. It initially found some false positives due to unusual constructs in a minority of tests; all such cases were disambiguated first in commit r186621.