Hello,

This patch adds tinyscheme as a coreboot payload. It adds some new functions to libpayload to support it.

Signed-off-by: Sylvain Ageneau <sylvain_ageneau@yahoo.fr>
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Dependency on dietlibc was completely removed.

The previous patch which adds math support to libpayload is not needed for this to work but then float/math support in tinyscheme needs to be disabled (currently the default).
If you'd rather not include the (minor) changes this patch makes to libpayload, please advise and I can move them to tinyscheme.

Regards,
Sylvain Ageneau