genymotion: fix startup on Qt-based environments
genymotion: fix startup on Qt-based environments

Currently trying to run Genymotion on Plasma 5 fails at all, Genymotion
itself complaining about libqtquickcontrols2materialstyleplugin.so using
"incompatible Qt library".
As it turns out, this package ships its own
version of Qt but does not ignore any environment variables related to
Qt, which results in Genymotion's Qt using (apparently incompatible)
QML plugins from user's system. This can be fixed quite easily by
unsetting `QML2_IMPORT_PATH` in a wrapper, which this patch does.
There might be more such problems, but I haven't encountered them yet,
so fixing those will be up to someone else ;)

NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs