fix(zynqmp): remove unused PLAT_NUM_POWER_DOMAINS

Remove unused PLAT_NUM_POWER_DOMAINS macro. Macro is referenced by
docs/design/psci-pd-tree.rst but it is not used in any calculation
that's why it is better to remove it.

Change-Id: I33f26cda6a4404061af5598ea4c751f64127e50a
Signed-off-by: Michal Simek <michal.simek@amd.com>
1 file changed