The distinction between 'ipc.h' and 'ipc_generic.h' is no more. The only
use case for platform-specific extensions of the IPC support was the
marshalling of capabilities. However, this case is accommodated by a
function interface ('_marshal_capability', '_unmarshal_capability'). By
moving the implementation of these functions from the headers into the
respective ipc libraries, we can abandon the platform-specific 'ipc.h'
headers.
Merge core only libs into the target make-files.
Use base-hw specific Board drivers that inherit
from generic Board_base.
Use Page_flags::access_t instead of additional
page_flags_t.
Fix#570