fatal error: 'device_if.h' file not found

[bob prohaska]

Hi,

The last two OS builds have reported
/usr/src/sys/sys/bus.h:655:10: fatal error: 'device_if.h' file not found
in buildkernel. It seemed possible to work around the missing file by
separately updating /usr/src/sys and re-running buildkernel, but the fix
didn't stick in the second iteration.

What am I doing wrong?

Many thanks,

bob prohaska