msc_a,vlr: rename ciphering_required to is_ciphering_to_be_attempted

Clarify the name to avoid confusion in upcoming patches.

This function actually returns whether any ciphering mode besides A5/0
is enabled, and does not imply that ciphering is mandatory. A5/0 may
well be allowed when this function returns true.

Related: OS#4830
Change-Id: Ia55085e3b36feb275bcf92fc91a4be7d1c24a6b9
diff --git a/include/osmocom/msc/msc_a.h b/include/osmocom/msc/msc_a.h
index f94420a..fd0aa08 100644
--- a/include/osmocom/msc/msc_a.h
+++ b/include/osmocom/msc/msc_a.h
@@ -180,7 +180,7 @@
 void msc_a_pending_cm_service_req_add(struct msc_a *msc_a, enum osmo_cm_service_type type);
 unsigned int msc_a_pending_cm_service_req_count(struct msc_a *msc_a, enum osmo_cm_service_type type);
 void msc_a_pending_cm_service_req_del(struct msc_a *msc_a, enum osmo_cm_service_type type);
-bool msc_a_require_ciphering(const struct msc_a *msc_a);
+bool msc_a_is_ciphering_to_be_attempted(const struct msc_a *msc_a);
 
 #define msc_a_ran_down(A,B,C) \
 	_msc_a_ran_down(A,B,C, __FILE__, __LINE__)