arm, dev: Add support for listing DMA ports in new platforms
arm, dev: Add support for listing DMA ports in new platforms

When using a Ruby memory system, the Ruby configuration scripts expect
to get a list of DMA ports to create the necessary DMA sequencers. Add
support in the utility functions that wire up devices to append DMA
ports to a list instead of connecting them to the IO bus. These
functions are currently only used by the VExpress_GEM5_V1 platform.

Change-Id: I46059e46b0f69e7be5f267e396811bd3caa3ed63
Signed-off-by: Andreas Sandberg <c9f5686ee5bd561c93f9de79681eee75bfa7f36e@arm.com>
Reviewed-by: Nikos Nikoleris <b6a1b3cd9d36c44e9eeb16bc870df3cb2a0cf469@arm.com>
Reviewed-by: Curtis Dunham <14490907fdc9c150c92157b82121c81003bbdc71@arm.com>
Reviewed-by: Brad Beckmann <b15a058fc1afc6d0fa0f02c7f237fa09d9ada29e@amd.com>

rallylee/gem5,sobercoder/gem5,Weil0ng/gem5,SanchayanMaity/gem5,Weil0ng/gem5,TUD-OS/gem5-dtu,Weil0ng/gem5,sobercoder/gem5,cancro7/gem5,cancro7/gem5,rjschof/gem5,TUD-OS/gem5-dtu,HwisooSo/gemV-update,SanchayanMaity/gem5,rallylee/gem5,TUD-OS/gem5-dtu,rallylee/gem5,gem5/gem5,Weil0ng/gem5,TUD-OS/gem5-dtu,aclifton/cpeg853-gem5,cancro7/gem5,rjschof/gem5,rjschof/gem5,gedare/gem5,HwisooSo/gemV-update,aclifton/cpeg853-gem5,SanchayanMaity/gem5,cancro7/gem5,TUD-OS/gem5-dtu,cancro7/gem5,gem5/gem5,sobercoder/gem5,aclifton/cpeg853-gem5,powerjg/gem5-ci-test,gem5/gem5,KuroeKurose/gem5,SanchayanMaity/gem5,KuroeKurose/gem5,rjschof/gem5,cancro7/gem5,gedare/gem5,KuroeKurose/gem5,sobercoder/gem5,HwisooSo/gemV-update,aclifton/cpeg853-gem5,Weil0ng/gem5,KuroeKurose/gem5,rallylee/gem5,powerjg/gem5-ci-test,SanchayanMaity/gem5,sobercoder/gem5,sobercoder/gem5,KuroeKurose/gem5,powerjg/gem5-ci-test,rallylee/gem5,aclifton/cpeg853-gem5,powerjg/gem5-ci-test,gedare/gem5,gem5/gem5,gedare/gem5,Weil0ng/gem5,TUD-OS/gem5-dtu,gedare/gem5,SanchayanMaity/gem5,rjschof/gem5,HwisooSo/gemV-update,cancro7/gem5,rjschof/gem5,Weil0ng/gem5,HwisooSo/gemV-update,KuroeKurose/gem5,TUD-OS/gem5-dtu,rallylee/gem5,powerjg/gem5-ci-test,SanchayanMaity/gem5,powerjg/gem5-ci-test,gem5/gem5,aclifton/cpeg853-gem5,gedare/gem5,sobercoder/gem5,HwisooSo/gemV-update,powerjg/gem5-ci-test,rallylee/gem5,aclifton/cpeg853-gem5,rjschof/gem5,gem5/gem5,gedare/gem5,HwisooSo/gemV-update,KuroeKurose/gem5,gem5/gem5