add LOG_RAN_CONN() to use the conn->fi->id for context

For each conn, set a default logging category, to distinguish categories for
BSSMAP and RANAP based conns.

LOG_RAN_CONN(): log with the conn's default category,

LOG_RAN_CONN_CAT(): log with a manually set category (mostly for keeping
previous DMM logging on the same category).

In some places, replace LOGP() using manual context with LOG_RAN_CONN(), and
remove the manual context info, now provided by the conn->fi->id.

This is loosely related to inter-BSC and inter-MSC handover: to speed up
refactoring, I want to avoid the need for manual logging context and just use
this LOG_RAN_CONN().

Change-Id: I0a7809840428b1e028df6eb683bc5ffcc8df474a
diff --git a/tests/msc_vlr/msc_vlr_tests.c b/tests/msc_vlr/msc_vlr_tests.c
index d3e338a..39d7e42 100644
--- a/tests/msc_vlr/msc_vlr_tests.c
+++ b/tests/msc_vlr/msc_vlr_tests.c
@@ -511,6 +511,11 @@
 		.description = "MNCC API for Call Control application",
 		.enabled = 1, .loglevel = LOGL_DEBUG,
 	},
+	[DBSSAP] = {
+		.name = "DBSSAP",
+		.description = "BSSAP Protocol (A Interface)",
+		.enabled = 1, .loglevel = LOGL_DEBUG,
+	},
 };
 
 static struct log_info info = {