TMP461: Add support for ADT7461 sensor

The register map is fairly similar, with one difference in the local
sensor temperature register width.
Both devices support reading two sensors - "local" and "remote".
While here add support for the latter one.
The ADT7461 doesn't update the temperature correctly, unless a write
transaction is done before every read.
Do just that as a workaround for this issue.

Tested on LS1046ARDB.

Reviewed by: manu
Obtained from: Semihalf
Differential Revision: https://reviews.freebsd.org/D36464