gprs_bssgp: rename gprs_ns_config -> gprs_ns_update_config

Improve the naming of the function to match it's purpose.

Related: SYS#5354
Change-Id: Ib8e4ae734503fd6f6695d9d6767d809e1bf79d22
diff --git a/src/gprs_bssgp_pcu.h b/src/gprs_bssgp_pcu.h
index 4b0e0aa..db77cbb 100644
--- a/src/gprs_bssgp_pcu.h
+++ b/src/gprs_bssgp_pcu.h
@@ -90,7 +90,7 @@
 		uint16_t mcc, uint16_t mnc, bool mnc_3_digits,
 		uint16_t lac, uint16_t rac, uint16_t cell_id);
 
-int gprs_ns_config(struct gprs_rlcmac_bts *bts, uint16_t nsei,
+int gprs_ns_update_config(struct gprs_rlcmac_bts *bts, uint16_t nsei,
 		   const struct osmo_sockaddr *local,
 		   const struct osmo_sockaddr *remote,
 		   uint16_t *nsvci, uint16_t valid);