Only add constants for parsing the Device Information subelement as that
is the main thing we care about in P2P code. And since our own WFD IEs
will likely only need to contain the Device Information subelement, we
don't need builder utilities. We do need iterator utilities because we
may receive WFD IEs with more subelements.
All these functions free up the resources used by the struct but don't
free the struct itself (allowing it to be static) so rename the
functions to avoid confusion.
The logic here intended to check whether all required attributes were
available. However, it set the parse_error to true instead of
have_required to false as intended.
Declare structures to hold the parsed contents of the P2P IEs and WSC
IEs in P2P-related frames and add functions to free memory used by
those structures.
Define structs and types for most P2P attributes and p2p_parse_attrs
similar to wsc_parse_attrs -- a generic parser for attributes in a P2P
IE payload. This parser may write into the provided buffer even on
error but it's private to p2putil.c. The local callers will take care
of keeping the user-provided buffers untouched on error.
