bootm: Support kernel_noload with compression

It is not currently possible to execute the kernel in-place without
loading it. Use lmb to allocate memory for it.

Co-developed-by: Tom Rini <trini@konsulko.com>
Signed-off-by: Simon Glass <sjg@chromium.org>
Suggested-by: Tom Rini <trini@konsulko.com>
Signed-off-by: Tom Rini <trini@konsulko.com>