Improve switch diagnostic to emit the "jump" message on the

specific bad case instead of on the switch.  Putting it on the
switch means you don't know what case is the problem. For 
example:

scope-check.c:54:3: error: illegal switch case into protected scope
  case 2:
  ^
scope-check.c:53:9: note: jump bypasses initialization of variable length array
    int a[x];
        ^

llvm-svn: 69462