The #if 0 code should be deleted. It's a copy of fins_isa_match code. In the ideal case the match would be done in fins.c using routines in fins_isa.c but there were no visible instances of non-isa chips. I'll blame my quick-and-dirty rework of the LM78 code for this blob.
The spec I worked from is http://www.fintek.com.tw/files/productfiles/F71872F_V026P.pdf As far as I can tell, the sensors part of the 71805 is the same as the 71872. If I had more examples to test I'd add checks for the other chips in this series. Is this what you were looking for? geoff