mem-garnet: Remove delete of param pointers of SimpleNetwork

mem-garnet: Remove delete of param pointers of SimpleNetwork

All over gem5 the params pointers are not deleted within the classes
that they were created for. Although this is a potential memory leak
as of now, it is probably safer to follow general convention so that
it can be fixed at once in the future.

Change-Id: If96f04058d51513fa8763610880e5524785ee9cf
Signed-off-by: Daniel R. Carvalho <odanrc@yahoo.com.br>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/24249
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Maintainer: Bobby R. Bruce <bbruce@ucdavis.edu>
Tested-by: kokoro <noreply+kokoro@google.com>