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>

 menu "Debug facilities"

 source "config.gen/debug.in"

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