fdt: Update functions which write to an FDT to return -ENOSPC

When writing values into an FDT it is possible that there will be
insufficient space. If the caller gets a useful error then it can
potentially deal with the situation.

Adjust these functions to return -ENOSPC when the FDT is full.

Signed-off-by: Simon Glass <sjg@chromium.org>
3 files changed