cbsp: Fix decoding of Fail List

The decoding pointer was not increased correctly, ending up in reading
by 1 byte offset  for each item in the list.

Change-Id: I16ed9bd65109a7ce32ff43c5789b4544479838e7
diff --git a/tests/testsuite.at b/tests/testsuite.at
index cc0b8c3..6b2e75f 100644
--- a/tests/testsuite.at
+++ b/tests/testsuite.at
@@ -108,6 +108,12 @@
 AT_CHECK([$abs_top_builddir/tests/smscb/gsm0341_test], [0], [expout])
 AT_CLEANUP
 
+AT_SETUP([smscb_cbsp])
+AT_KEYWORDS([smscb_cbsp])
+cat $abs_srcdir/smscb/cbsp_test.ok > expout
+AT_CHECK([$abs_top_builddir/tests/smscb/cbsp_test], [0], [expout])
+AT_CLEANUP
+
 AT_SETUP([ussd])
 AT_KEYWORDS([ussd])
 cat $abs_srcdir/ussd/ussd_test.ok > expout