Fail linking when there are undefined symbols upon producing the shared library.

Signed-off-by: Jean-Paul Saman <jean-paul.saman@m2x.nl>
(cherry picked from commit a9c4f543)

src/Makefile.am

@@ -11,7 +11,7 @@ libdvbpsi_la_SOURCES = dvbpsi.c dvbpsi_private.h \
                        $(tables_src) \
                        $(descriptors_src)
 
-libdvbpsi_la_LDFLAGS = -version-info 7:0:0
+libdvbpsi_la_LDFLAGS = -version-info 7:0:0 -Wl,--no-undefined
 
 pkginclude_HEADERS = dvbpsi.h psi.h descriptor.h demux.h \
                      tables/pat.h tables/pmt.h tables/sdt.h tables/eit.h \