feat(qemu): update abi between spmd and spmc

feat(qemu): update abi between spmd and spmc

Updates the ABI between SPMD and the SPMC at S-EL1 so that the hard
coded SPMC manifest can be replaced by a proper manifest via TOS FW
Config. TOS FW Config is provided via QEMU_TOS_FW_CONFIG_DTS as a DTS
file when building.  The DTS is turned into a DTB which is added to the
FIP.

Note that this is an incompatible change and requires corresponding
change in OP-TEE ("core: sel1 spmc: boot abi update").

Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
Change-Id: Ibabe78ef50a24f775492854ce5ac54e4d471e369