tests: Add x86 mutlicore boot tests for timing CPUs

Due to a spin lock error affecting multicore timing cores,
https://gem5.atlassian.net/browse/GEM5-1105, gem5 only supported
single-core timing setups. As this has now been fixed, we support it.
This patch expands the boot tests to include tests for multicore timing
CPU systems.

Change-Id: I89b7f1bed077373dae5e9b8eb6818129da915fee
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/55744
Reviewed-by: Austin Harris <mail@austin-harris.com>
Reviewed-by: Jason Lowe-Power <power.jg@gmail.com>
Maintainer: Jason Lowe-Power <power.jg@gmail.com>
Maintainer: Bobby Bruce <bbruce@ucdavis.edu>
Tested-by: kokoro <noreply+kokoro@google.com>

tests/gem5/x86-boot-tests/test_linux_boot.py

@@ -125,6 +125,15 @@ test_boot(
     length=constants.quick_tag,
 )
 
+test_boot(
+    cpu="timing",
+    num_cpus=8,
+    mem_system="classic",
+    memory_class="SingleChannelDDR3_2133",
+    to_tick=10000000000,
+    length=constants.quick_tag,
+)
+
 test_boot(
     cpu="atomic",
     num_cpus=4,
@@ -172,6 +181,15 @@ test_boot(
     length=constants.long_tag,
 )
 
+test_boot(
+    cpu="timing",
+    num_cpus=4,
+    mem_system="classic",
+    memory_class="DualChannelDDR3_2133",
+    boot_type="init",
+    length=constants.long_tag,
+)
+
 test_boot(
     cpu="atomic",
     num_cpus=4,
@@ -224,15 +242,15 @@ run_map = {
         },
         "timing": {
             1: True,
-            2: False,  # Timeout
-            4: False,  # Timeout
-            8: False,  # Timeout
+            2: True,
+            4: True,
+            8: True,
         },
         "o3": {
             1: False,  # Timeout
-            2: False,  # Not Supported
-            4: False,  # Not Supported
-            8: False,  # Not Supported
+            2: False,  # Timeout
+            4: False,  # Timeout
+            8: False,  # Timeout
         },
     },
     "mi_example": {