libc/uClibc: add uClibc 0.9.30.3

This version has been released a couple of month ago, but it never reached
crosstool-ng tree. This may be linked to the fact that the current 0.9.30.2,
once patched, has nothing much different from 0.9.30.3, released.

I'm not including any patch with this upgrade, on purpose.

Signed-off-by: Arnaud Lacombe <lacombar@gmail.com>

 # Blackfin specific configuration file

 config ARCH_blackfin

     select ARCH_SUPPORTS_32

     select ARCH_DEFAULT_32

     select ARCH_DEFAULT_LE

     select ARCH_SUPPORT_ARCH

     select ARCH_SUPPORT_CPU

     select ARCH_SUPPORT_TUNE

     select ARCH_SUPPORT_FPU

      help

       The Blackfin architecture