firmware: arm_ffa: Split up ffa_ops into info, message and memory operations

firmware: arm_ffa: Split up ffa_ops into info, message and memory operations

In preparation to make memory operations accessible for a non
ffa_driver/device, it is better to split the ffa_ops into different
categories of operations: info, message and memory. The info and memory
are ffa_device independent and can be used without any associated
ffa_device from a non ffa_driver.

However, we don't export these info and memory APIs yet without the user.
The first users of these APIs can export them.

Link: https://lore.kernel.org/r/20220907145240.1683088-11-sudeep.holla@arm.com
Reviewed-by: Jens Wiklander <jens.wiklander@linaro.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>