Move while stmt from block stmt 2 keywords to other in emacs major mode.

Make while an other keyword (c-other-kwds) in emacs major mode instead of block
stmt with 2 keywords (c-block-stmt-2-kwds). Before this change, the indentation
for the block of while loops that did not surround the conditional in
parenthesis was broken.

This while loop shows the issue. Before the fix, this is the indentation:

```chpl
while (x % 2 != 1) {
  writeln("nothing");
 }
while x % 2 != 1 {
  writeln("nothing");
          }
```

With this fix, the indentation is correct with and without parens:

```chpl
while (x % 2 != 1) {
  writeln("nothing");
}
while x % 2 != 1 {
  writeln("nothing");
}
```

### TODO:

* [ ] Verify indentation is correct on more complex programs with while loops.