PPC: Fixing the EmptyFreeListCategoriesRemoved test on pLinux and AIX

Original commit: 303ca9ac

Change-Id: I276bc68253fe4cedecdd2a77db0e8dbbc998c1a5
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1652504Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Commit-Queue: Milad Farazmand <miladfar@ca.ibm.com>
Cr-Commit-Position: refs/heads/master@{#62125}

test/cctest/heap/test-spaces.cc

@@ -795,6 +795,7 @@ HEAP_TEST(AllocateObjTinyFreeList) {
 }
 
 HEAP_TEST(EmptyFreeListCategoriesRemoved) {
+  ManualGCScope manual_gc_scope;
   CcTest::InitializeVM();
   Isolate* isolate = CcTest::i_isolate();
   HandleScope scope(isolate);