VLR: log subscriber update

* move log helpers to generic header
* log subscriber update

It's handy for troubleshooting issues with subscriber update via GSUP
from HLR.

Change-Id: I1958aeeb3ea99831c7e2c5ee9a6b59834baf4520
diff --git a/include/osmocom/msc/vlr.h b/include/osmocom/msc/vlr.h
index d68b7be..b4bb27f 100644
--- a/include/osmocom/msc/vlr.h
+++ b/include/osmocom/msc/vlr.h
@@ -12,6 +12,12 @@
 // for GSM_NAME_LENGTH
 #include <osmocom/msc/gsm_subscriber.h>
 
+#define LOGGSUPP(level, gsup, fmt, args...)				\
+	LOGP(DVLR, level, "GSUP(%s) " fmt, (gsup)->imsi, ## args)
+
+#define LOGVSUBP(level, vsub, fmt, args...)				\
+	LOGP(DVLR, level, "SUBSCR(%s) " fmt, vlr_subscr_name(vsub), ## args)
+
 struct log_target;
 
 /* from 3s to 10s */