configs: Fix signature in GPU_VIPER and Garnet_standalone

This was broken by:

https://gem5-review.googlesource.com/c/public/gem5/+/43287

Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Change-Id: I0ac64cfe64cefd6c6ad8a9e7d00def00ee967136
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/43746
Reviewed-by: Matt Sinclair <mattdsinclair@gmail.com>
Reviewed-by: Jason Lowe-Power <power.jg@gmail.com>
Maintainer: Jason Lowe-Power <power.jg@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>

configs/ruby/Garnet_standalone.py

@@ -40,7 +40,7 @@ def define_options(parser):
     return
 
 def create_system(options, full_system, system, dma_ports, bootmem,
-                  ruby_system):
+                  ruby_system, cpus):
     if buildEnv['PROTOCOL'] != 'Garnet_standalone':
         panic("This script requires Garnet_standalone protocol to be built.")