o reduce the extra-long ID names.
o TI-1510, 1520 and 4510 support.
o MFUNC is the name of the register on TI 1200 and newer chips (except
125x and 1450). Initialize it in the func routine, but only
if NO_MFUNC isn't set.
o better comments about above workaround
o register definitions for MFUNC.
o move zoom video disable to a better place.