arch: Decentralize the arch tag TagImplies in arch/SConscript.

Put the TagImplies for each ISA in its own SConscript.

Change-Id: I90d72aa6f493ac2c27ec54e3ac02ff8151e2f518
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/52494
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Tested-by: kokoro <noreply+kokoro@google.com>
7 files changed