extern optind etc already declared in unistd.h

[Jan Stary]

extern optind and friends are already declared
once unistd.h is included, to these can be removed.

This is the usr.sbin part; I am not touching nsd
and other third-party stuff.

        Jan


Index: usr.sbin//yppoll/yppoll.c
===================================================================
RCS file: /cvs/src/usr.sbin/yppoll/yppoll.c,v
retrieving revision 1.15
diff -u -p -r1.15 yppoll.c
--- usr.sbin//yppoll/yppoll.c   16 Jan 2015 06:40:22 -0000      1.15
+++ usr.sbin//yppoll/yppoll.c   22 Nov 2021 23:06:04 -0000
@@ -126,8 +126,6 @@ int
 main(int argc, char *argv[])
 {
        char *domainname, *hostname = NULL, *inmap, *master;
-       extern char *optarg;
-       extern int optind;
        int order, c, r;
        time_t torder;
 
Index: usr.sbin//ypserv/makedbm/makedbm.c
===================================================================
RCS file: /cvs/src/usr.sbin/ypserv/makedbm/makedbm.c,v
retrieving revision 1.33
diff -u -p -r1.33 makedbm.c
--- usr.sbin//ypserv/makedbm/makedbm.c  9 Feb 2015 23:00:15 -0000       1.33
+++ usr.sbin//ypserv/makedbm/makedbm.c  22 Nov 2021 23:06:04 -0000
@@ -302,9 +302,6 @@ main(int argc, char *argv[])
        char    *infile, *outfile;
        int     ch;
 
-       extern int optind;
-       extern char *optarg;
-
        yp_input_file = yp_output_file = NULL;
        yp_master_name = yp_domain_name = NULL;
        aflag = uflag = bflag = lflag = sflag = Uflag = 0;
Index: usr.sbin//ypserv/yppush/yppush.c
===================================================================
RCS file: /cvs/src/usr.sbin/ypserv/yppush/yppush.c,v
retrieving revision 1.31
diff -u -p -r1.31 yppush.c
--- usr.sbin//ypserv/yppush/yppush.c    16 Jan 2015 06:40:23 -0000      1.31
+++ usr.sbin//ypserv/yppush/yppush.c    22 Nov 2021 23:06:04 -0000
@@ -216,8 +216,6 @@ int
 main(int argc, char *argv[])
 {
        struct ypall_callback ypcb;
-       extern char *optarg;
-       extern int optind;
        char    *domain, *map, *hostname;
        int c, r, i;
        char *ypmap = "ypservers";
Index: usr.sbin//ypset/ypset.c
===================================================================
RCS file: /cvs/src/usr.sbin/ypset/ypset.c,v
retrieving revision 1.20
diff -u -p -r1.20 ypset.c
--- usr.sbin//ypset/ypset.c     16 Jan 2015 06:40:23 -0000      1.20
+++ usr.sbin//ypset/ypset.c     22 Nov 2021 23:06:04 -0000
@@ -106,8 +106,6 @@ main(int argc, char *argv[])
 {
        struct sockaddr_in sin;
        struct hostent *hent;
-       extern char *optarg;
-       extern int optind;
        char *domainname;
        int c;