[PATCH] `iwlist scan` fails with many networks available

In 5.x it's still possible for `ieee80211_scan_results` (`iwlist
scan`) to fail when too many wireless networks are available.  This
code path is used by `wicd`.

Previously: https://lkml.org/lkml/2017/4/2/192

I've been applying this updated patch to my own kernels since 2017 with
no issues.  I am sure it is not the ideal way to solve this problem, but
I'm making my fix available in case it helps others.

Please advise on next steps or if this is a dead end.