[Mesa-maintainers] Removal of unused configure options.

[Emil Velikov]

Hi all,

Some of you may know/have noticed that a couple of configure options
were removed with the 17.0 series.

In particular:
--with-sha1=libc|libmd|libnettle|libgcrypt|libcrypto|libsha1|CommonCrypto|CryptoAPI
--disable-shader-cache

Due to a number of reasons we've imported a sha1 implementation in
mesa thus the dependencies should no longer be required.
Note that the code in question is always enabled and I would strongly
urge that you test it via `make check' and report any issues.

Thanks
Emil