getopt.3 / getopt_long.3: Remove NOTREACHED comment as per style(9)

[Juuso Lapinlampi]

style(9) revision 1.61 updated the guidelines, and mentions the only 
lint-style comment that should be used is FALLTHROUGH.

Ok?

Index: getopt.3
===================================================================
RCS file: /cvs/src/lib/libc/stdlib/getopt.3,v
retrieving revision 1.44
diff -u -p -u -r1.44 getopt.3
--- getopt.3    21 Jan 2014 03:15:45 -0000      1.44
+++ getopt.3    4 Jan 2016 11:29:45 -0000
@@ -183,7 +183,6 @@ while ((ch = getopt(argc, argv, "bf:")) 
                break;
        default:
                usage();
-               /* NOTREACHED */
        }
 }
 argc -= optind;
Index: getopt_long.3
===================================================================
RCS file: /cvs/src/lib/libc/stdlib/getopt_long.3,v
retrieving revision 1.20
diff -u -p -u -r1.20 getopt_long.3
--- getopt_long.3       5 Jun 2013 03:39:23 -0000       1.20
+++ getopt_long.3       4 Jan 2016 11:29:45 -0000
@@ -420,7 +420,6 @@ while ((ch = getopt_long(argc, argv, "bf
                break;
        default:
                usage();
-               /* NOTREACHED */
        }
 argc -= optind;
 argv += optind;