Delete unused YieldProcessorScalingFactor from GC (dotnet#23994)

Author: jkotas

src/gc/gc.h

@@ -141,8 +141,6 @@ extern "C" uint32_t g_num_processors;
 
 extern VOLATILE(int32_t) g_fSuspensionPending;
 
-extern uint32_t g_yieldProcessorScalingFactor;
-
 ::IGCHandleManager*  CreateGCHandleManager();
 
 namespace WKS {

src/gc/gccommon.cpp

@@ -37,8 +37,6 @@ uint32_t* g_gc_card_table;
 
 VOLATILE(int32_t) g_fSuspensionPending = 0;
 
-uint32_t g_yieldProcessorScalingFactor = 1;
-
 #ifdef FEATURE_MANUALLY_MANAGED_CARD_BUNDLES
 uint32_t* g_gc_card_bundle_table;
 #endif

src/gc/gcpriv.h

@@ -4563,14 +4563,3 @@ size_t gcard_of (uint8_t* object)
 {
     return (size_t)(object) / card_size;
 }
-
-inline
-void YieldProcessorScalingFactor()
-{
-    unsigned int n = g_yieldProcessorScalingFactor;
-    _ASSERTE(n != 0);
-    do
-    {
-        YieldProcessor();
-    } while (--n != 0);
-}