With earlier commit (install-lib-links: don't depend on .libs directory)
we moved the location of the file from .libs/ to the current dir.
Although we did not attribute that in the former case autotools was
doing us a favour and removing the file. Explicitly remove the file at
clean-local time, otherwise we'll end up with dangling files.

Cc: "10.3 10.4 10.5" <mesa-stable@lists.freedesktop.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Lucas Stach <l.stach@pengutronix.de>
Signed-off-by: Emil Velikov <emil.l.velikov@gmail.com>