Clean up the code a bit.

Clean up the code a bit.

This eliminates a warning from MSVC, and makes the flow a little
clearer.

(Yes, it duplicates some code, but compilers have been pretty good at
merging common code sequences, so it might just turn it into the
equivalent of

	if (optopt == (int)':')
		goto label;
	oli = strchr(ostr, optopt);
	if (!oli) {
	label:
		/*
		 * Unknown option character.
		 */
		if (!*place)
			++optind;

		...
	}

although it does mean that the same C code exists in two places.)