ARM: PL08x: allow AHB master port selection to be configured

Platforms need to be able to control which AHB master interface is used,
as each AHB master interface may be asymetric.  Allow the interfaces
used for fetching LLIs, memory, and each peripheral to be configured
individually.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>