OemPkg: Remove StackCheckLib instance since its inherited from MdeLibs.dsc.inc

Author: apop5

OemPkg/OemPkg.dsc

@@ -89,10 +89,6 @@
 [LibraryClasses.IA32]
   MsUiThemeLib|MsGraphicsPkg/Library/MsUiThemeLib/Pei/MsUiThemeLib.inf
 
-[LibraryClasses.AARCH64]
-  # Add support for GCC stack protector
-  NULL|MdePkg/Library/BaseStackCheckLib/BaseStackCheckLib.inf
-
 [LibraryClasses.common.DXE_DRIVER, LibraryClasses.common.UEFI_APPLICATION]
   HobLib|MdePkg/Library/DxeHobLib/DxeHobLib.inf
   PolicyLib|PolicyServicePkg/Library/DxePolicyLib/DxePolicyLib.inf