This change make the following commands correctly detect the 4B
however there may be an issue with reading GPIO inputs on the 4B
as they are always returning zero.

The aim of this change is to be the source-equivalent of the binary
package release 2.52[1] which was the last release before upstream
development ceased.

[1] http://wiringpi.com/wiringpi-updated-to-2-52-for-the-raspberry-pi-4b/