fix map entry for gsm0808_speech_codec_from_chan_type

Recent commit 884ba0f2bcaf385cabee0b4228a2598d61fa406b adds function
gsm0808_chan_type_to_speech_codec() but adds a mismatching name in
libosmogsm.map. openbsc.git's aoip branch can't build with this.

This must have been an on-the-fly rename that wasn't properly tested. Always
test your patches!

Change-Id: I68feb14f7bcb2f62b89f9b2d8c085d6824b493bc
diff --git a/src/gsm/libosmogsm.map b/src/gsm/libosmogsm.map
index 2da8649..e992a4f 100644
--- a/src/gsm/libosmogsm.map
+++ b/src/gsm/libosmogsm.map
@@ -163,7 +163,7 @@
 gsm0808_enc_cell_id_list;
 gsm0808_dec_cell_id_list;
 gsm0808_chan_type_to_speech_codec;
-gsm0808_extrapolate_speech_codec;
+gsm0808_speech_codec_from_chan_type;
 
 gsm0858_rsl_ul_meas_enc;