replace linkfile functionality with command-line options

Instead of running:
$ xlink linkfile.txt
where the linkfile looks like:
---
[Objects]
foo.o
bar.o

[Libraries]
foo.l
bar.l

[Output]
baz.gb
---
we now do:
$ xlink -o baz.gb -l foo.l -l bar.l foo.o bar.o

src/link/main.c

@@ -118,19 +118,23 @@ main(int argc, char *argv[])
 	int ch;
 	char *ep;
 
-	SLONG argn = 0;
-
 	if (argc == 1)
 		usage();
 
-	while ((ch = getopt(argc, argv, "m:n:s:t:z:")) != -1) {
+	while ((ch = getopt(argc, argv, "l:m:n:o:s:t:z:")) != -1) {
 		switch (ch) {
+		case 'l':
+			lib_Readfile(optarg);
+			break;
 		case 'm':
 			SetMapfileName(optarg);
 			break;
 		case 'n':
 			SetSymfileName(optarg);
 			break;
+		case 'o':
+			out_Setname(optarg);
+			break;
 		case 's':
 			options |= OPT_SMART_C_LINK;
 			strcpy(smartlinkstartsymbol, optarg);
@@ -171,16 +175,18 @@ main(int argc, char *argv[])
 	argc -= optind;
 	argv += optind;
 
-	if (argc == 1) {
-		ProcessLinkfile(argv[argc - 1]);
+	if (argc == 0)
+		usage();
+
+	for (int i = 0; i < argc; ++i)
+		obj_Readfile(argv[i]);
+
 	AddNeededModules();
 	AssignSections();
 	CreateSymbolTable();
 	Patch();
 	Output();
 	CloseMapfile();
-	} else
-		usage();
 
 	return (0);
 }