Reenable internal pointers for <= warm opt level

Internal pointers are never actually disabled for <= warm level until
recent refactoring in OMR changed it to use the correct API and disbled
it for real. Disabling internal pointers for <= warm opt level would
hurt performance so we need to enable it.

pr: eclipse-omr#2715

Signed-off-by: Yi Zhang <yizhang@ca.ibm.com>

compiler/compile/OMRCompilation.cpp

@@ -919,15 +919,7 @@ int32_t OMR::Compilation::compile()
    bool printCodegenTime = self()->getOption(TR_CummTiming);
 
    if (self()->isOptServer())
-      {
-      // Temporarily exclude PPC due to perf regression
-      if( (self()->getMethodHotness() <= warm))
-         {
-         if (!TR::Compiler->target.cpu.isPower())
-            self()->getOptions()->setOption(TR_DisableInternalPointers);
-         }
       self()->getOptions()->setOption(TR_DisablePartialInlining);
-      }
 
 #ifdef J9_PROJECT_SPECIFIC
    if (self()->getOptions()->getDelayCompile())