UMTS_FP: fix handling reserved C/T value

The spec puts the reserved value at 0xf but our internal table has 'unknown' at
0; since all the other values seem to be offset-by-one, just take the modulus
0xf to avoid running off the end of the table.

Bug: 12191
Change-Id: I83c8fb66797bbdee52a2246fb1eea6e37cbc7eb0
Reviewed-on: https://code.wireshark.org/review/15722
Reviewed-by: Evan Huus <eapache@gmail.com>
Petri-Dish: Evan Huus <eapache@gmail.com>
Tested-by: Petri Dish Buildbot <buildbot-no-reply@wireshark.org>
Reviewed-by: Michael Mann <mmann78@netscape.net>
dissect_common_outer_loop_power_control(packet_info *pinfo, proto_tree *tree, tvbuff_t *tvb,
                                        int offset, struct fp_info *p_fp_info _U_)
{
    return dissect_dch_outer_loop_power_control(tree, pinfo, tvb, offset);
}

dissect_common_outer_loop_power_control(packet_info *pinfo, proto_tree *tree, tvbuff_t *tvb,
                                        int offset, struct fp_info *p_fp_info _U_)
{
    return dissect_dch_outer_loop_power_control(tree, pinfo, tvb, offset);
}
