dbus: revert changes to some peer properties

dbus: revert changes to some peer properties

Commit 3f6e50ac282bbcb4be137023316543bd232ba350 made it possible to access
P2P peer properties using the org.freedesktop.DBus.Properties interface.

While maintaining the original intent of that patch we make two changes
to it here:

First, 3f6e50ac282bbcb4be137023316543bd232ba350 changed the type used to
represent the WPS vendor extension data from bytes to a string. In
addition to the type change the way in which the vendor extension data
was provided to the function creating the string was incorrect and would
not present the correct vendor extension data even in string format.

Revert the type change made in 3f6e50ac282bbcb4be137023316543bd232ba350
and present the WPS vendor extension data as an array of an array of
bytes as it was before.

Second, 3f6e50ac282bbcb4be137023316543bd232ba350 changes the secondary
device types representation from an array of an array of bytes to an
array of bytes. Revert that change to make secondary device types
accessible via an array of an array of bytes again.

Signed-hostap: Reinette Chatre <reinette.chatre@intel.com>
intended-for: hostap-1