Build onnxruntime.dll as arm64x
Added a .cmake file to generate a link repro of the onnxruntime.dll
during arm64 build. This provides us a directory containing all the
arm64 objs, def file and libs to link to when it is time to building
arm64x onnxruntime.dll during the arm64ec build by passing the
/machine:arm64x flag to the linker along with the arm64 artifacts.
If other dlls wanted to be built as x, setting the ARM64X_TARGETS
variable in the toplevel cmakelists.txt to include these other targets
is all that will be needed.
Added build_arm64x.bat as a wrapper for the multiple (rm64, then
arm64ec) cmake calls needed to build as arm64x.
AB#22533
moyo1997