The supplied path for executing the shell client could contain potential
arguments and not only the binary itself. Specifying the platform either
by using an argument (-platform wayland) or using an environmental
variable (QT_QPA_PLATFORM) with clients written in Qt is for instance
an example on why this might be useful to have in.
Signed-off-by: Marius Vlad <marius.vlad@collabora.com>