CPack: re-use paths of tools discovered by CMakeFindBinUtils

`CMakeFindBinUtils.cmake` sets `CMAKE_<TOOL>` variables that in
cross-compilation environments point to the toolchain specific
executables: e.g. `CMAKE_OBJCOPY` might point to
`<path_to_toolchain>/arm-poky-linux-gnueabi-objcopy`.
Pass this information to CPack.
10 files changed