cpu: Fix import in O3 CheckerCPU

ArmMMU isn't defined in ArmTLB

Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Change-Id: Idc33720303d20cf6176e6ec6d17197661526eb2e
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/46620
Reviewed-by: Richard Cooper <richard.cooper@arm.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>

src/cpu/o3/O3CPU.py

@@ -178,7 +178,7 @@ class O3CPU(BaseCPU):
 
     def addCheckerCpu(self):
         if buildEnv['TARGET_ISA'] in ['arm']:
-            from m5.objects.ArmTLB import ArmMMU
+            from m5.objects.ArmMMU import ArmMMU
 
             self.checker = O3Checker(workload=self.workload,
                                      exitOnError=False,