kdf: add key derivation functions

generic sha code from git://w1.fi/hostap.git commit
5ea93947ca67ba83529798b806a15b247cdb2e93 which also happens
to be the source of our milenage code.

Related: SYS#5324
Change-Id: Ibf2e49edada944d91ceba62bd0d6b6ce69261fcd
diff --git a/src/gsm/libosmogsm.map b/src/gsm/libosmogsm.map
index 3fd01db..437599b 100644
--- a/src/gsm/libosmogsm.map
+++ b/src/gsm/libosmogsm.map
@@ -547,6 +547,12 @@
 osmo_auth_c3;
 osmo_sub_auth_type_names;
 
+osmo_kdf_kc128;
+osmo_kdf_kasme;
+osmo_kdf_enb;
+osmo_kdf_nh;
+osmo_kdf_nas;
+
 osmo_rsl2sitype;
 osmo_sitype2rsl;