Annotate the USB transfer creation functions with the correct buffer
access attribute. Note that we only annotate them as read_only as the
functions may be used for sending and receiving.
Hopefully this will catch buffer overflows in drivers in the future.
Don't make headers inclusions dependent on each others, given that FpiSsm
depends on FpiUsbTransfer and vice-versa, so fix the dependency cycle by
using forwarded declarations.
This is a rewrite of the core based on GObject and Gio. This commit
breaks the build in a lot of ways, but basic functionality will start
working again with the next commits.
