shell32: Fix ShellExecute for non-filespec paths
I was going to reimplement path resolution in ShellExecute, but half way through I realized that's very unnecessary.
Since what I wanted is a version of PathResolve
that behaves differently only for filespec paths, I ended up duplicating a lot of code, then I realized I can still pass filespec paths onto PathResolve
and only deal with non-filespec paths.