[CMake] ToolChain file scope

[dfurtney at cox.net]

I have been hammergin on a vxworks cross-compile toolchain file. It seems that not all properties that are set in the cross-compilation file propogate to the CMakeLists.txt file that is using it. An example is the CMAKE_AR property.  Setting it in the cross-compilation file had no effect and the value during linking of a static library was "'. Once I moved it to the CMakeLists.txt file the setting was recognized. Setting of library prefix and postfix values seemed to behave the same way.

These things seem like reasonable targets for the cross-compilation file so I am confused as to why they wouldn't work. Any help is appreciated.