arch-vega: Remove ASID parameter from Requests

The ASID parameter was removed from the Request class header while the
Vega patches were under review and these were not updated.

Change-Id: Ie04027bac09a63063501a49ec438b69628972b2d
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/47101
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Matt Sinclair <mattdsinclair@gmail.com>
Reviewed-by: Bobby R. Bruce <bbruce@ucdavis.edu>
Maintainer: Matt Sinclair <mattdsinclair@gmail.com>
2 files changed