KVM: selftests: Remove unneeded semicolon

Remove unnecessary semicolons reported by Coccinelle/coccicheck and the
semantic patch at scripts/coccinelle/misc/semicolon.cocci.

Signed-off-by: Chen Ni <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Sean Christopherson <[e-mail]>

tools/testing/selftests/kvm/access_tracking_perf_test.c

···
 		case ITERATION_MARK_IDLE:
 			mark_vcpu_memory_idle(vm, vcpu_args);
 			break;
-		};
+		}
 
 		vcpu_last_completed_iteration[vcpu_idx] = current_iteration;
 	}