Introduce a VTY, factually turning OpenGGSN into an Osmocom program

Change-Id: I9613ca3436e77ea132c47f0096df7c5050d7e826
diff --git a/ggsn/Makefile.am b/ggsn/Makefile.am
index c945f0b..fef12d3 100644
--- a/ggsn/Makefile.am
+++ b/ggsn/Makefile.am
@@ -2,17 +2,17 @@
 
 AM_LDFLAGS = @EXEC_LDFLAGS@
 
-AM_CFLAGS = -O2 -D_GNU_SOURCE -fno-builtin -Wall -DSBINDIR='"$(sbindir)"' -ggdb $(LIBOSMOCORE_CFLAGS) $(LIBOSMOCTRL_CFLAGS)
+AM_CFLAGS = -O2 -D_GNU_SOURCE -fno-builtin -Wall -DSBINDIR='"$(sbindir)"' -ggdb $(LIBOSMOCORE_CFLAGS) $(LIBOSMOCTRL_CFLAGS) $(LIBOSMOVTY_CFLAGS)
+
+ggsn_LDADD = @EXEC_LDADD@ -lgtp -L../gtp ../lib/libmisc.a $(LIBOSMOCORE_LIBS) $(LIBOSMOCTRL_LIBS) $(LIBOSMOVTY_LIBS)
 
 if ENABLE_GTP_KERNEL
 AM_CFLAGS += -DGTP_KERNEL
-ggsn_LDADD = @EXEC_LDADD@ -lgtp -lgtpnl -L../gtp ../lib/libmisc.a $(LIBOSMOCORE_LIBS) $(LIBOSMOCTRL_LIBS)
-else
-ggsn_LDADD = @EXEC_LDADD@ -lgtp -L../gtp ../lib/libmisc.a $(LIBOSMOCORE_LIBS) $(LIBOSMOCTRL_LIBS)
+ggsn_LDADD += -lgtpnl
 endif
 
 ggsn_DEPENDENCIES = ../gtp/libgtp.la ../lib/libmisc.a
-ggsn_SOURCES = ggsn.c cmdline.c cmdline.h gtp-kernel.h icmpv6.c icmpv6.h checksum.c checksum.h
+ggsn_SOURCES = ggsn_vty.c ggsn.c ggsn.h gtp-kernel.h icmpv6.c icmpv6.h checksum.c checksum.h
 
 if ENABLE_GTP_KERNEL
 ggsn_SOURCES += gtp-kernel.c