libpwquality: select cracklib

libpwquality: select cracklib

libpwquality adds cracklib to its _DEPENDENCIES, but forgot to select it in
Config.in, leading to build failures if cracklib isn't explicitly enabled:

Makefile:536: *** cracklib is in the dependency chain of libpwquality that
has added it to its _DEPENDENCIES variable without selecting it or depending
on it from Config.in.  Stop.

No autobuilder references as this error happens before build-time.log is
written, causing the autobuilder to ignore the build result.

Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
Acked-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>