interconnect: qcom: Add multiple voter support

Add support for targeting alternate bcm-voters which
live under different RSC devices.

Change-Id: Ia1ad8a4c6c6b8531f0dae67cc7b22e2faa55c418
Signed-off-by: David Dai <daidavid1@codeaurora.org>
Signed-off-by: Georgi Djakov <gdjako@codeaurora.org>