deby.conf: Override QB_DTB
deby.conf: Override QB_DTB

Deby uses linux-base but Poky sets QB_DTB base on PREFERRED_VERSION_linux-yocto.
If version of linux-yocto > 4.7, QB_DTB will be set to zImage-versatile-pb.dtb
which is not available in the current linux-base.

Empty QB_DTB to fix error when runqemu with qemuarm:
  | Exception: DTB not found: ...

Signed-off-by: Trung Do <64081e6b7eb2b24289b8a4e51cef9836ddf28af2@toshiba-tsdv.com>
Signed-off-by: Kazuhiro Hayashi <d6ab13038406a238a56011921c4eda80a48396fd@toshiba.co.jp>

meta-debian/meta-debian,meta-debian/meta-debian,meta-debian/meta-debian,meta-debian/meta-debian,meta-debian/meta-debian,meta-debian/meta-debian