logging: use new harald's logging infrastructure in libosmocore

I can send patches to improve it later, better not to waste
much time at it by now so port libosmo-abis upon it.
diff --git a/tests/ipa_proxy_test.c b/tests/ipa_proxy_test.c
index cea8e2b..755eec8 100644
--- a/tests/ipa_proxy_test.c
+++ b/tests/ipa_proxy_test.c
@@ -13,7 +13,7 @@
 
 static void *tall_test;
 
-#define DIPA_PROXY_TEST OSMO_LOG_SS_APPS
+#define DIPA_PROXY_TEST 0
 
 struct log_info_cat ipa_proxy_test_cat[] = {
 	[DIPA_PROXY_TEST] = {