bug#28732: flymake mouse-wheel portability fix

[Eli Zaretskii]

> From: Noam Postavsky <npostavs@gmail.com>
> Cc: Eli Zaretskii <eliz@gnu.org>,  rgm@gnu.org,  28732@debbugs.gnu.org
> Date: Thu, 01 Mar 2018 21:10:50 -0500
> 
> charles@aurox.ch (Charles A. Roelli) writes:
> 
> >> Is there any reason you cannot simply require mwheel in flymake?  Or
> >> does loading mwheel in a --without-x build fail?
> >
> > Good point.  Can someone with a "--without-x" build handy check that?
> > "mwheel.elc" is in src/lisp.mk, so it confuses me that it would not be
> > immediately available.
> 
> mwheel loads without errors for me in a --without-x build.

Thanks, I pushed the required change.