x86_64: Make pcie vcfg size same as pcie ECAM size
x86_64: Make pcie vcfg size same as pcie ECAM size

Pcie vcfg use similiar pcie ECAM to distribute vcfg mmio into
each pci device, in order to make each pci device has such pcie
vcfg mmio, its size should be same as pcie ECAM.

BUG=b:194391459
TEST=check each device's pcie vcfg mmio in guest

Change-Id: I1ca13384514f323b1e49decd3de198bdfa3ac347
Reviewed-on: https://chromium-review.googlesource.com/c/crosvm/crosvm/+/3813135
Reviewed-by: Victor Ding <b4a7cab2b204d4052366cc26438aa3555eb3d577@chromium.org>
Reviewed-by: Daniel Verkamp <72bc170b46ec491f7bdd4359a1c0bfed274de40c@chromium.org>
Tested-by: Daniel Verkamp <72bc170b46ec491f7bdd4359a1c0bfed274de40c@chromium.org>

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