[chirp_devel] Luiton LT-725UV Patch

Attached is the patch for issues #4645, #5407 and #5595, adding support for the Baojie BJ-218 clones to the Luiton LT-725UV driver. This update and patch has been blessed by Jim Unroe. I may have gotten carried away with style fixes and changed some of the original driver comments to first char uppercase, instead of just my new ones. I am so ashamed....