[ccache] basename of source file in hashed name in ccache

[Joel Rosdahl]

On 2011-12-20 20:09, Frank Klotz wrote:
> Suggestion: Put the below 2-line solution in the "Corrupt object
> files" section of http://ccache.samba.org/manual.html [...] It's a LOT
> lighter-weight solution than clearing the cache, and much easier than
> messing with the log.

Good suggestion. I'll do that in the next version.

-- Joel