MdePkg/BaseCpuLib: Remove assembly for CpuFlushTlb

For different compilers, both IA32 and X64 can use
Ia32/CpuFlushTlbGcc.c, which is C code (no inline assembly code).
To simplify, remove other assemly file for CpuFlushTlb,
and rename Ia32/CpuFlushTlbGcc.c to X86CpuFlushTlb.c.

Reviewed-by: Michael D Kinney <michael.d.kinney@intel.com>
Cc: Liming Gao <gaoliming@byosoft.com.cn>
Signed-off-by: Ray Ni <ray.ni@intel.com>
Signed-off-by: Zhiguang Liu <zhiguang.liu@intel.com>

MdePkg/Library/BaseCpuLib/X64/CpuFlushTlb.nasm

@@ -1,32 +0,0 @@
-;------------------------------------------------------------------------------ ;
-; Copyright (c) 2006, Intel Corporation. All rights reserved.<BR>
-; SPDX-License-Identifier: BSD-2-Clause-Patent
-;
-; Module Name:
-;
-;   CpuFlushTlb.Asm
-;
-; Abstract:
-;
-;   CpuFlushTlb function
-;
-; Notes:
-;
-;------------------------------------------------------------------------------
-
-    DEFAULT REL
-    SECTION .text
-
-;------------------------------------------------------------------------------
-; VOID
-; EFIAPI
-; CpuFlushTlb (
-;   VOID
-;   );
-;------------------------------------------------------------------------------
-global ASM_PFX(CpuFlushTlb)
-ASM_PFX(CpuFlushTlb):
-    mov     rax, cr3
-    mov     cr3, rax
-    ret
-