The 'environment' word is too long. We mostly use 'env' in U-Boot, so use
that as the name of the include directory too.
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> # Intel Edison
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
