evil: Remove OS version check

Summary:
Current version checking is done with GetVersion, which is now deprecated and issues the warning:

'GetVersion' is deprecated [-Wdeprecated-declarations]

The first approach of this commit was to replace GetVersion call with the newer (and more reliable) IsWindowsVistaOrGreater() from versionhelpers.h, but nowadays it makes more sense to actually not even make that check, since it is more than unlinkely to happen that someone tries to compile/run EFL in Windows XP.

Reviewers: vtorri, stefan_schmidt, raster

Reviewed By: vtorri, raster

Subscribers: cedric, reviewers, committers

Tags: efl

Differential Revision: https://phab.enlightenment.org/D12095