contrib: remove udbachk.tgz

Having source code in a compressed file doesn't seem like a good idea. I
checked several distributions and they don't distribute this binary, so
let's remove it.

Signed-off-by: Iker Pedrosa <ipedrosa@redhat.com>

contrib/Makefile.am

@@ -1,5 +1,4 @@
 # This is a dummy Makefile.am to get automake work flawlessly,
 # and also cooperate to make a distribution for `make dist'
 
-EXTRA_DIST = README adduser.c adduser.sh adduser2.sh \
- udbachk.tgz
+EXTRA_DIST = README adduser.c adduser.sh adduser2.sh