Fixes FTBFS when libmenu-cache was installed to non-standard location
Fixes FTBFS when libmenu-cache was installed to non-standard location

libmenu-cache pkg-config file defines Cflags as:
    Cflags: -I${includedir}/menu-cache
So #include <menu-cache/menu-cache.h> works only if ${includedir} is
included by default, e.g. standard locations. When libmenu-cache was
installed to a non-standard location ${includedir} is not part of the
default include path and #include <menu-cache/menu-cache.h> fails.

lxde/lxqt-runner,stefonarch/lxqt-runner