Blackfin support:

Blackfin support:
* siteinfo.bbclass, bfin-common: autofoo support
* kernel-arch.bbclass, linux-libc-headers_2.6.20.bb: bfin -> blackfin mapping for the kernel
* insane.bbclass: stubs for bfin arch, needs proper number, but that will get reported when it encounters the first binary
* uclibc: config for adsp-bf537-stamp machine
* adsp-bf537-stamp.conf: machine description for adsp-bf537-stamp board (http://www.analog.com/en/prod/0%2C2877%2CBF537%25252DSTAMP%2C00.html)
The build currently stops in binutils cross with the "ld not supported on this archicture" message