classes: bundle: Allow parsing var flags offset, hooks and adaptive
classes: bundle: Allow parsing var flags offset, hooks and adaptive

Allow for BitBake variable parsing inside the variable flags "offset",
"hooks" and "adaptive". To enable this, use d.getVarFlag() instead of
the builtin get() method.

Signed-off-by: Martin Schwan <0b4b17d835f86924185dc5770bd021250822e547@phytec.de>

rauc/meta-rauc,rauc/meta-rauc,rauc/meta-rauc,rauc/meta-rauc