tests: Move old quick regressions back into their original set

tests: Move old quick regressions back into their original set

realview64-simple-atomic and realview64-simple-timing had been moved
to the long list by:

https://gem5-review.googlesource.com/c/public/gem5/+/22686

in order to reduce computation time.
Since the timeout has been increased on kokoro we can safely put them
back where they were

Change-Id: Ib86f02b8ef493f450509b9f826a80faaec9ef579
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/25025
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Bobby R. Bruce <bbruce@ucdavis.edu>
Tested-by: kokoro <noreply+kokoro@google.com>