PSCI: Fix types of definitions

Also change header guards to fix defects of MISRA C-2012 Rule 21.1.

Change-Id: Ied0d4b0e557ef6119ab669d106d2ac5d99620c57
Acked-by: Sumit Garg <sumit.garg@linaro.org>
Acked-by: Anson Huang <Anson.Huang@nxp.com>
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>
27 files changed