Adds support for SHM_REGISTER IOCTL. Registration can
be requested both against the driver (for automatic cleanup)
and against the secure OS (for sharing).
Introduces also `optee_{msg,free}_alloc()` to allocate
aligned memory for message arguments depending on the
`alignment` specified in the driver's private data. For
alignment greater than word size, memory is allocated on the
heap, otherwise it's allocated on the stack (similar to the
previous implementation but using `alloca()` instead).
Signed-off-by: George Poulios <gpoulios@census-labs.com>
Prepares the ground for introducing new transports to
the OP-TEE driver. "transports" as in alternatives to
RPMsg and local network.
Signed-off-by: George Poulios <gpoulios@census-labs.com>
