cosmetic: get rid of 3 deprecation warnings

Some deprecated functions are still used in libosmocore .c code. Use
OSMO_DEPRECATED_OUTSIDE() to get rid of those "resident warnings".

Change-Id: I6e79acc87be37ac1aaec900e737e41450b46826a
diff --git a/include/osmocom/core/counter.h b/include/osmocom/core/counter.h
index dc62791..0d56bc4 100644
--- a/include/osmocom/core/counter.h
+++ b/include/osmocom/core/counter.h
@@ -31,7 +31,7 @@
 }
 
 /*! Get current value of counter */
-OSMO_DEPRECATED("Implement as osmo_stat_item instead")
+OSMO_DEPRECATED_OUTSIDE("Implement as osmo_stat_item instead")
 static inline unsigned long osmo_counter_get(struct osmo_counter *ctr)
 {
 	return ctr->value;