CONTRIBUTING: fix CROSS_COMPILE example
This was missing the `arm-none-eabi-` prefix.
@@ -179,7 +179,7 @@ sure that the cross-compiler can be found. This can be done by adding it to the
Or by setting the `CROSS_COMPILE` environment variable:
- export CROSS_COMPILE=$install_dir/gcc-arm-none-eabi-*/bin
+ export CROSS_COMPILE=$install_dir/gcc-arm-none-eabi-*/bin/arm-none-eabi-
`$install_dir` needs to be replaced with the actual directory where you
actually installed the toolchain.
