uboot-phytec

malloc_simple: Add debug() information

It's useful to get a a trace of memory allocations in early init. Add a
debug() call to provide that. It can be enabled by adding '#define DEBUG'
to the top of the file.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>