[chirp_devel] [PATCH][BTECH] Simplified second ID proc, add QYT KT-8900, fixes #3015

In this patch: - Simplified the procedure for the second ID of some radios in preparation to add the QYT KT-8900 radio. - Added support for the QYT KT-8900. - Fixing the variable naming for the QYT KT-UV980.

Also related to issue #2673 (support for the QYT KT-8900)