WDM driver builds should include 'shared' WDK header directory

[acyr]

xmake/xmake/rules/wdk/env/load.lua

Line 112 in 6046c05

kmdf(target)

Some headers under km/ depend on those in shared/ as well from the WDK, so the shared/ include path must also be included in system path.
I believe this should work:

 target:add("sysincludedirs", path.join(wdk.includedir, wdk.sdkver, "shared")) 

[waruqi]

I don't have a WDK environment. You can submit a PR directly.