[ofw] changes in tools\wsdinstall\user\installsp.c

[Fab Tillier]

The local variable errno was renamed to err_no.  This introduces changes to the source that as far as I can tell are not actually useful. What was the purpose of this change?  Is it (again) to work around a development tool limitation?

Please stop introducing code changes unless they're actually useful, and if you must, separate cleanup into specific cleanup patches.

-Fab