pcie: Fix bridge window's mmio alignment
pcie: Fix bridge window's mmio alignment

Bridge window's mmio alignment went wrong during our refactor, fix
it in this commit.

BUG=b:185084350
TEST=Check bridge window and pci device mmio setting in CrOS

Change-Id: Ia1a01d1740f943ec7aa36812defe3aabffcfcbde
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/crosvm/+/3498219
Reviewed-by: Daniel Verkamp <72bc170b46ec491f7bdd4359a1c0bfed274de40c@chromium.org>
Tested-by: kokoro <2ac7b1f3fa578934c95181d4272be0d3bca00121@google.com>
Commit-Queue: Daniel Verkamp <72bc170b46ec491f7bdd4359a1c0bfed274de40c@chromium.org>

google/crosvm,google/crosvm,google/crosvm,google/crosvm