oap_client: move logging to DLOAP logging category

Use libosmocore's DLOAP logging category for OAP.

oap_client_test.c: make sure DLOAP is in DEBUG level to not lose any logging
messages from experr.

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

Related: OS#1592
Change-Id: Ic765c19381b0d983da90a5d8aee9cd17e31cf34a
diff --git a/openbsc/tests/oap/oap_client_test.err b/openbsc/tests/oap/oap_client_test.err
index 3272237..248808e 100644
--- a/openbsc/tests/oap/oap_client_test.err
+++ b/openbsc/tests/oap/oap_client_test.err
@@ -3,26 +3,26 @@
 - reset state
 - only client_id is invalid
 - valid id, but omitted shared_secret (1/2)
-DGPRS OAP: client ID set, but secret K missing.
+DLOAP OAP: client ID set, but secret K missing.
 - valid id, but omitted shared_secret (2/2)
-DGPRS OAP: client ID set, but secret OPC missing.
+DLOAP OAP: client ID set, but secret OPC missing.
 - mint configuration
 - Missing challenge data
-DGPRS OAP challenge incomplete (rand_present: 0, autn_present: 0)
+DLOAP OAP challenge incomplete (rand_present: 0, autn_present: 0)
 - AUTN missing
-DGPRS OAP challenge incomplete (rand_present: 1, autn_present: 0)
+DLOAP OAP challenge incomplete (rand_present: 1, autn_present: 0)
 - RAND missing
-DGPRS OAP challenge incomplete (rand_present: 0, autn_present: 1)
+DLOAP OAP challenge incomplete (rand_present: 0, autn_present: 1)
 - wrong autn (by one bit)
-DGPRS OAP: AUTN mismatch!
-DGPRS OAP: AUTN from server: dec4e3848a33000086781158ca40f136
-DGPRS OAP: AUTN expected:    cec4e3848a33000086781158ca40f136
+DLOAP OAP: AUTN mismatch!
+DLOAP OAP: AUTN from server: dec4e3848a33000086781158ca40f136
+DLOAP OAP: AUTN expected:    cec4e3848a33000086781158ca40f136
 - all data correct
 - but refuse to evaluate in uninitialized state
 - now everything is correct
 - Expect the challenge response in msg_tx
 - Receive registration error for the first time.
-DGPRS OAP registration failed
+DLOAP OAP registration failed
 - Receive registration error for the Nth time.
-DGPRS OAP registration failed
+DLOAP OAP registration failed
 - Registration success