lsm: rename variable to avoid shadowing

The function dump_common_audit_data() contains two variables with the
name comm: one declared at the top and one nested one.  Rename the
nested variable to improve readability and make future refactorings
of the function less error prone.

Signed-off-by: Christian Göttsche <cgzones@googlemail.com>
[PM: description long line removal, line wrap cleanup, merge fuzz]
Signed-off-by: Paul Moore <paul@paul-moore.com>