Fix devstack default settings in aarch64

1. Lack qemu-efi in ubuntu
2. Lack edk2.git-aarch64 in Fedora/Centos
3. Remove NOVNC disable.

Change-Id: Ifbd0c386df6b28bc64cef20cab8e08f99a85c782
Signed-off-by: Kevin Zhao <kevin.zhao@linaro.org>
2 files changed