plat/synquacer: enable SCMI support ...

Enable the SCMI protocol support in SynQuacer platform.
Aside from power domain, system power and apcore management protocol,
this commit adds the vendor specific protocol(0x80).
This vendor specific protocol is used to get the dram mapping information
from SCP.

Signed-off-by: Masahisa Kojima <masahisa.kojima@linaro.org>

Minor changes to documentation and comments ...

Fix some typos and clarify some sentences.

Change-Id: Id276d1ced9a991b4eddc5c47ad9a825e6b29ef74
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

plat/arm: sds: Move to drivers/ folder ...

Change-Id: Ia601d5ad65ab199e747fb60af4979b7db477d249
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

plat/arm: scp: Move to drivers/ folder ...

Change-Id: Ida5dae39478654405d0ee31a6cbddb4579e76a7f
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

plat/arm: scpi: Move to drivers/ folder ...

Change-Id: Icc59cdaf2b56f6936e9847f1894594c671db2e94
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

plat/arm: mhu: Move to drivers/ folder ...

Change-Id: I656753a1825ea7340a3708b950fa6b57455e9056
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

plat/arm: scmi: Move to drivers/ folder ...

Change-Id: I8989d2aa0258bf3b50a856c5b81532d578600124
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>