msm: VPU: Attach VPU SMMUs within fixed powerup sequence

Attach VPU SMMUs inside the boot work sequence, such that it's
order is fixed relative to other VPU power up operations.

Change-Id: I86771d5289b864c937425153fa3894b2f24d8ff6
Signed-off-by: Ahmed Abdul-Salam <aabdulsa@codeaurora.org>