As SOS has already adapted to the new state transition of VHM requests for a
month, the old `valid` field can now be safely obsoleted.
This patch changes the `valid` field as reserved and drops all the code that
reads or modifies this field for backward compatibility. The embedded comments
are updated accordingly, following the doxygen style.
Tracked-On: #875
Signed-off-by: Junjie Mao <junjie.mao@intel.com>
Acked-by: Eddie Dong <eddie.dong@intel.com>