test(memory share): hypervisor retrieve request

Checks that the hypervisor retrieve request from section 17.4.3 of FF-A
v1.2 REL0 is supported.

Specifically, the tests:
1. Sends a FFA_MEM_SHARE/FFA_MEM_LEND/FFA_MEM_DONATE message from the
   tftf target to the SPMC.
2. Sends a hypervisor retrieve request from the tftf target to the SPMC.
3. Verify the contents of the FFA_MEM_RETRIEVE_RESP message against the
   previously sent message.
4. Invoke reclaim interface for SPMC to free memory owned by the handle.

Change-Id: If27d8d5b515c5e468977ed4f5f4ddeb86e44c5df
Signed-off-by: Karl Meakin <karl.meakin@arm.com>
6 files changed