meta-openembedded has gtk4 which has its own version of
gtk-update-icon-cache. Allow programs that want to use gtk4
use the proper version of the gtk-update-icon-cache utility
and the proper build and runtime dependencies.
Also use a more readable syntax for conditional values in DEPENDS.
Signed-off-by: Zoltán Böszörményi <zboszor@gmail.com> Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
