Ticket #185 (Check for gethostbyname with nsl)

socket.m4: add nsl in search for gethostbyname

m4.include/vfs/socket.m4

@@ -1,8 +1,8 @@
 AC_DEFUN([AC_REQUIRE_SOCKET],
 [
     AC_SEARCH_LIBS(socket, [xnet bsd socket inet], [have_socket=yes])
-    if test x"$have_socket" = xyes; then
-      AC_SEARCH_LIBS(gethostbyname, [bsd socket inet netinet])
+    if test x"$have_socket" = x"yes"; then
+      AC_SEARCH_LIBS(gethostbyname, [bsd socket inet netinet nsl])
       AC_CHECK_MEMBERS([struct linger.l_linger], , , [
 #include <sys/types.h>
 #include <sys/socket.h>