Give getopt() a prototype and modern style arg specs.

Welcome to the 1990s.

src/port/getopt.c

@@ -61,6 +61,8 @@ extern char *optarg;
 #define BADARG	(int)':'
 #define EMSG	""
 
+int getopt(int nargc, char *const * nargv, const char * ostr);
+
 /*
  * getopt
  *	Parse argc/argv argument vector.
@@ -72,10 +74,7 @@ extern char *optarg;
  * returning -1.)
  */
 int
-getopt(nargc, nargv, ostr)
-int			nargc;
-char	   *const * nargv;
-const char *ostr;
+getopt(int nargc, char *const * nargv, const char * ostr)
 {
 	static char *place = EMSG;	/* option letter processing */
 	char	   *oli;			/* option letter list index */