musl: add getopt support for non-option arguments

musl libc doesn't support the GNU getopt extension to parse non-option
arguments when the optstring starts with '-'.

This extension is used by some utilities, notably iptables, that
currently return with errors even with perfectly valid invocations.

The patch adds the code needed by getopt.c and getopt_long.c to
implement that extension.

Signed-off-by: Gianluca Anzolin <gianluca@sottospazio.it>

SVN-Revision: 43309

toolchain/musl/patches/120-getopt_non-option-arguments_fix.patch

@@ -0,0 +1,43 @@
+--- a/src/misc/getopt.c
++++ b/src/misc/getopt.c
+@@ -24,8 +24,23 @@ int getopt(int argc, char * const argv[]
+ 		optind = 1;
+ 	}
+ 
+-	if (optind >= argc || !argv[optind] || argv[optind][0] != '-' || !argv[optind][1])
++	if (optind >= argc || !argv[optind])
+ 		return -1;
++
++	if (argv[optind][0] != '-') {
++		/* GNU extension */
++		if (optstring[0] == '-') {
++			optarg = argv[optind];
++			optind++;
++			return 1;
++		}
++
++		return -1;
++	}
++
++	if (!argv[optind][1])
++		return -1;
++
+ 	if (argv[optind][1] == '-' && !argv[optind][2])
+ 		return optind++, -1;
+ 
+--- a/src/misc/getopt_long.c
++++ b/src/misc/getopt_long.c
+@@ -12,7 +12,12 @@ static int __getopt_long(int argc, char
+ 		__optpos = 0;
+ 		optind = 1;
+ 	}
+-	if (optind >= argc || !argv[optind] || argv[optind][0] != '-') return -1;
++	if (optind >= argc || !argv[optind])
++		return -1;
++
++	if (argv[optind][0] != '-')
++		return getopt(argc, argv, optstring);
++
+ 	if ((longonly && argv[optind][1]) ||
+ 		(argv[optind][1] == '-' && argv[optind][2]))
+ 	{