Preserve suid/gid permissions when extracting packages remotelly

fetched with -r option

Reviewed by:	will
Approved by:	will

usr.sbin/pkg_install/lib/file.c

@@ -222,7 +222,7 @@ fileGetURL(const char *base, const char *spec)
 	dup2(pfd[0], 0);
 	for (fd = getdtablesize() - 1; fd >= 3; --fd)
 	    close(fd);
-	execl("/usr/bin/tar", "tar", Verbose ? "-xzvf" : "-xzf", "-",
+	execl("/usr/bin/tar", "tar", Verbose ? "-xzpvf" : "-xzpf", "-",
 	    (char *)0);
 	_exit(2);
     }