gbproxy: Pass the log level as argument to gprs_gb_log_parse_context

Currently, the log level is always LOGL_DEBUG. In case of errors it
would be helpful to use a higher log level.

This patch adds a log_level parameter to gprs_gb_log_parse_context to
let the caller decide about the level.

Ticket: OW#1307
Sponsored-by: On-Waves ehf
diff --git a/openbsc/src/gprs/gb_proxy.c b/openbsc/src/gprs/gb_proxy.c
index 1437646..59771fa 100644
--- a/openbsc/src/gprs/gb_proxy.c
+++ b/openbsc/src/gprs/gb_proxy.c
@@ -566,7 +566,7 @@
 	gbprox_update_current_raid(parse_ctx.bssgp_raid_enc, peer,
 				   parse_ctx.llc_msg_name);
 
-	gprs_gb_log_parse_context(&parse_ctx, "BSSGP");
+	gprs_gb_log_parse_context(LOGL_DEBUG, &parse_ctx, "NS_UNITDATA");
 
 	link_info = gbproxy_update_link_state_ul(peer, now, &parse_ctx);
 
@@ -668,7 +668,7 @@
 		}
 	}
 
-	gprs_gb_log_parse_context(&parse_ctx, "BSSGP");
+	gprs_gb_log_parse_context(LOGL_DEBUG, &parse_ctx, "NS_UNITDATA");
 
 	link_info = gbproxy_update_link_state_dl(peer, now, &parse_ctx);