patch: add all-byte and install-byte targets

[ecc1]

This patch allows building on architectures without native code compilers. It fixes Debian bug #616176.

http://anonscm.debian.org/gitweb/?p=pkg-ocaml-maint/packages/ocaml-sha.git;a=blob_plain;f=debian/patches/0004-add-all-byte-and-install-byte-targets.patch;hb=HEAD

[talex5]

I guess this will be fixed as a side-effect of #29.