Add support for DEBUG_LL on the 8660 and 8960 development boards.
While we're here cleanup the uncompress.h code a bit. Avoid
the use of readl/writel as those are Linux specific APIs that
aren't guaranteed to work in the decompressor.

Cc: Nicolas Pitre <nico@fluxnic.net>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Acked-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: David Brown <davidb@codeaurora.org>