The BaseTools/Scripts/ConvertMasmToNasm.py script was used to convert
X64/EbcLowLevel.asm to X64/EbcLowLevel.nasm
And, manually update nasm code to use mov rcx, dword value and generate
the same assembly code with rcx register to asm code.
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Jordan Justen <jordan.l.justen@intel.com>