buildroot

bash: security bump to patchlevel 25

Fixes CVE-2014-6271:

Under certain circumstances, bash will execute user code while
processing the environment for exported function definitions.

Also add hash file.

Signed-off-by: Gustavo Zacarias <gustavo@zacarias.com.ar>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>