GitLab

This patch fixes a compilation issue for platforms that are aligned to ARM
Standard platforms and include the `plat_arm.h` header in their platform port.
The compilation would fail for such a platform because `xlat_tables.h` which
has the definition for `mmap_region_t` is not included in `plat_arm.h`. This
patch fixes this by including `xlat_tables.h` in `plat_arm.h` header.

Fixes ARM-Software/tf-issues#318

Change-Id: I75f990cfb4078b3996fc353c8cd37c9de61d555e