Move ClearFirst4KPage/IsNullDetectionEnabled definition from DxeIpl.h to
VirtualMemory.h as they are implemented in VirtualMemory.c and only used
in IA32/X64 ARCH.
Cc: Jian J Wang <jian.j.wang@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Star Zeng <star.zeng@intel.com>
Reviewed-by: Jian J Wang <jian.j.wang@intel.com>
ac733f313b