Depend on libosmocore 0.1.31 due to VTY / logging change
diff --git a/openbsc/configure.in b/openbsc/configure.in
index 4cd1952..8afce17 100644
--- a/openbsc/configure.in
+++ b/openbsc/configure.in
@@ -43,8 +43,8 @@
     ])
 AM_CONDITIONAL(BUILD_BSC, test "x$osmo_ac_build_bsc" = "xyes")
 
-PKG_CHECK_MODULES(LIBOSMOCORE, libosmocore >= 0.1.30)
-PKG_CHECK_MODULES(LIBOSMOVTY, libosmovty >= 0.1.28)
+PKG_CHECK_MODULES(LIBOSMOCORE, libosmocore >= 0.1.31)
+PKG_CHECK_MODULES(LIBOSMOVTY, libosmovty >= 0.1.31)
 
 dnl checks for header files
 AC_HEADER_STDC