- changed x11 to wl as suitable displayserver option for ARM based projects
- changed the WINDOWMANAGER var from "none" to "no" if it's not in use to us the same naming scheme as for all other vars
- set the WINDOWMANAGER for generic/wayland to weston
valgrind is only included if VALGRIND is explicitly set to "yes",
setting it to "no" in some options files is not needed.
Signed-off-by: Matthias Reichl <hias@horus.com>