gsup client, gsup_test_client: move logging to DLGSUP category

Use the DLGSUP logging category for GSUP.

Bump the required version of libosmocore to 0.9.5 to benefit from the DLGSUP
logging category fix in core/logging.[hc].
(Id974c7be158e4d60421a98110f5c807aefd31119)

Todo: we're using a "Library" logging category, which is not really what the
library category was intended for. Instead, the GSUP client should probably be
given a logging category like DVLR or DGPRS in its initialization API.

Related: OS#1592
Change-Id: Id3938267fa062e1a997d3704cd678874306f86ee
diff --git a/openbsc/configure.ac b/openbsc/configure.ac
index 123048f..4fe1050 100644
--- a/openbsc/configure.ac
+++ b/openbsc/configure.ac
@@ -30,7 +30,7 @@
 AC_SUBST(LIBRARY_DL)
 
 
-PKG_CHECK_MODULES(LIBOSMOCORE, libosmocore >= 0.9.4)
+PKG_CHECK_MODULES(LIBOSMOCORE, libosmocore >= 0.9.5)
 PKG_CHECK_MODULES(LIBOSMOVTY, libosmovty >= 0.3.0)
 PKG_CHECK_MODULES(LIBOSMOCTRL, libosmoctrl)
 PKG_CHECK_MODULES(LIBOSMOGSM, libosmogsm >= 0.9.4)