sdp_msg: add sdp_audio_codecs_cmp(), add compare flags

A problem with SDP fmtp handling is visible in this patch: when cmp_fmtp
is true, we compare fmtp strings 1:1, which is not how things should be
done. The intention is to fix fmtp handling in a later patch.

At least there now is a flag to bypass fmtp comparison altogether.

Related: SYS#5066
Change-Id: I18d33e189674229501afec950aa1c732386455a2
diff --git a/include/osmocom/msc/sdp_msg.h b/include/osmocom/msc/sdp_msg.h
index 44a8a30..537713c 100644
--- a/include/osmocom/msc/sdp_msg.h
+++ b/include/osmocom/msc/sdp_msg.h
@@ -36,7 +36,10 @@
 
 const char *sdp_msg_line_end(const char *src);
 
-int sdp_audio_codec_cmp(const struct sdp_audio_codec *a, const struct sdp_audio_codec *b);
+int sdp_audio_codec_cmp(const struct sdp_audio_codec *a, const struct sdp_audio_codec *b,
+			bool cmp_fmtp, bool cmp_payload_type);
+int sdp_audio_codecs_cmp(const struct sdp_audio_codecs *a, const struct sdp_audio_codecs *b,
+			 bool cmp_fmtp, bool cmp_payload_type);
 
 struct sdp_audio_codec *sdp_audio_codec_add(struct sdp_audio_codecs *ac, unsigned int payload_type,
 					    const char *subtype_name, unsigned int rate, const char *fmtp);