Revert "assignment_fsm: Properly support assigning signalling mode TCH/x"

This commit breaks voice channel assignment. It results in the
Assignment Complete sent to the MSC for a voice lchan lacking
AoIP Transport Layer Address, Speech Version and Speech Codec.
Hence the MSC cannot complete the Assignment for a voice call.
Let's revisit this patch, test thoroughly and re-merge later.

This reverts commit 4d3a21269b25e7164a94fa8ce3ad67ff80904aee.

Reason for revert: <INSERT REASONING HERE>

Change-Id: I72aaa03539919e7e85b5b75b133326cec5e68bc9
diff --git a/tests/codec_pref/codec_pref_test.c b/tests/codec_pref/codec_pref_test.c
index ce82f3d..bb5468a 100644
--- a/tests/codec_pref/codec_pref_test.c
+++ b/tests/codec_pref/codec_pref_test.c
@@ -407,7 +407,7 @@
 
 	rc = match_codec_pref(&ch_mode_rate, ct, scl, msc, bts, RATE_PREF_NONE);
 	printf(" * result: rc=%i, full_rate=%i, s15_s0=%04x, chan_mode=%s\n",
-	       rc, ch_mode_rate.chan_rate == CH_RATE_FULL, ch_mode_rate.s15_s0, gsm48_chan_mode_name(ch_mode_rate.chan_mode));
+	       rc, ch_mode_rate.full_rate, ch_mode_rate.s15_s0, gsm48_chan_mode_name(ch_mode_rate.chan_mode));
 
 	printf("\n");