rework /debian support to match new osmo-sgsn

Remove old leftover from split of osmo-sgsn out of openbsc.

Change-Id: Ic0135a1118a115e8f053154e280f60674390f43a
diff --git a/debian/osmo-gtphub.install b/debian/osmo-gtphub.install
index 908c1a5..8a5dafd 100644
--- a/debian/osmo-gtphub.install
+++ b/debian/osmo-gtphub.install
@@ -1 +1,2 @@
-/usr/bin/osmo-gtphub
+usr/bin/osmo-gtphub
+usr/share/doc/openbsc/examples/osmo-gtphub