Revert "gb: Fix naming and export symbol bssgp_enc_rim_pdu"

This reverts commit 43ad616e4b66913eedc54f136addcc961b6402f8.

 _enc_ functions are for some ies while the _encode_ and _decode_ are
for the full pdu.  so the old name is correct.

Change-Id: Ib0b4a6fd7f8c96e4647a373541e3cccb324c6a11
diff --git a/include/osmocom/gprs/gprs_bssgp_rim.h b/include/osmocom/gprs/gprs_bssgp_rim.h
index 41d7982..5f397c9 100644
--- a/include/osmocom/gprs/gprs_bssgp_rim.h
+++ b/include/osmocom/gprs/gprs_bssgp_rim.h
@@ -267,6 +267,6 @@
 };
 
 int bssgp_parse_rim_pdu(struct bssgp_ran_information_pdu *pdu, const struct msgb *msg);
-struct msgb *bssgp_enc_rim_pdu(const struct bssgp_ran_information_pdu *pdu);
+struct msgb *bssgp_encode_rim_pdu(const struct bssgp_ran_information_pdu *pdu);
 
 int bssgp_tx_rim(const struct bssgp_ran_information_pdu *pdu, uint16_t nsei);