tests: Removed tests/halt.sh

`tests/halt.sh` is a duplicate of `configs/tests/halt.sh`. The one
instance of using `halt.sh`, `tests/gem5/fs/linux/arm/run.py`, has been
updated to use `configs/tests/halt.sh` and `tests/halt.sh` has been
removed.

Change-Id: I42f77a22b5985959a579c75541e4a0fdc135aa0c
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/33135
Reviewed-by: Jason Lowe-Power <power.jg@gmail.com>
Reviewed-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Maintainer: Jason Lowe-Power <power.jg@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>

tests/gem5/fs/linux/arm/run.py

@@ -67,7 +67,7 @@ sys.path.append(joinpath(tests_root, 'configs'))
 exec(compile(open(config).read(), config, 'exec'))
 
 system = root.system
-system.readfile = os.path.join(tests_root, 'halt.sh')
+system.readfile = os.path.join(gem5_root, 'configs', 'boot', 'halt.sh')
 
 # The CPU can either be a list of CPUs or a single object.
 if isinstance(system.cpu, list):

tests/halt.sh

@@ -1 +0,0 @@
-m5 exit