Arm FF-A fixes for v6.4

Quite a few fixes to address set of assorted issues:
1. NULL pointer dereference if the ffa driver doesn't provide remove()
   callback as it is currently executed unconditionally
2. FF-A core probe failure on systems with v1.0 firmware as the new
   partition info get count flag is used unconditionally
3. Failure to register more than one logical partition or service within
   the same physical partition as the device name contains only VM ID
   which will be same for all but each will have unique UUID.
4. Rejection of certain memory interface transmissions by the receivers
   (secure partitions) as few MBZ fields are non-zero due to lack of
   explicit re-initialization of those fields

* tag 'ffa-fixes-6.4' of git://git.kernel.org/pub/scm/linux/kernel/git/sudeep.holla/linux:
  firmware: arm_ffa: Set reserved/MBZ fields to zero in the memory descriptors
  firmware: arm_ffa: Fix FFA device names for logical partitions
  firmware: arm_ffa: Fix usage of partition info get count flag
  firmware: arm_ffa: Check if ffa_driver remove is present before executing

Link: https://lore.kernel.org/r/20230509143453.1188753-1-sudeep.holla@arm.com
Signed-off-by: Arnd Bergmann <arnd@arndb.de>