Simplify musl's getopt, including removing optind, optopt, opterr, idx, and longonly

Author: Rangi42

include/extern/getopt.hpp

@@ -12,7 +12,7 @@ static constexpr int optional_argument = 2;
 // clang-format on
 
 extern char *musl_optarg;
-extern int musl_optind, musl_opterr, musl_optopt, musl_optreset;
+extern int musl_optind, musl_optopt;
 
 struct option {
 	char const *name;
@@ -21,8 +21,6 @@ struct option {
 	int val;
 };
 
-int musl_getopt_long_only(
-    int argc, char **argv, char const *optstring, option const *longopts, int *idx
-);
+int musl_getopt_long_only(int argc, char **argv, char const *optstring, option const *longopts);
 
 #endif // RGBDS_EXTERN_GETOPT_HPP

src/cli.cpp

@@ -94,8 +94,7 @@ void cli_ParseArgs(
 	for (;;) {
 		char *atFileName = nullptr;
 		for (int ch;
-		     (ch = musl_getopt_long_only(curArgc, curArgv, optString.c_str(), longOpts, nullptr))
-		     != -1;) {
+		     (ch = musl_getopt_long_only(curArgc, curArgv, optString.c_str(), longOpts)) != -1;) {
 			if (ch == 1 && musl_optarg[0] == '@') {
 				atFileName = &musl_optarg[1];
 				break;