tools: gtp-link: rename file now that we support deletion command

Better name for what this simple tool does.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

tools/Makefile.am

@@ -1,10 +1,10 @@
 include $(top_srcdir)/Make_global.am
 
-check_PROGRAMS = gtp-link-add		\
+check_PROGRAMS = gtp-link		\
 		 gtp-tunnel
 
-gtp_link_add_SOURCES = gtp-link-add.c
-gtp_link_add_LDADD = ../src/libgtpnl.la ${LIBMNL_LIBS}
+gtp_link_SOURCES = gtp-link.c
+gtp_link_LDADD = ../src/libgtpnl.la ${LIBMNL_LIBS}
 
 gtp_tunnel_SOURCES = gtp-tunnel.c
 gtp_tunnel_LDADD = ../src/libgtpnl.la ${LIBMNL_LIBS}