rpm: Turn on debugging

rpm: Turn on debugging

Now that we build with a blank CFLAGS line, we need to make sure and
actually turn on debugging in the build system, so that our debuginfo
files are vaguely useful

Reviewed-on: http://gerrit.openafs.org/5662
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Derrick Brashear <shadow@dementix.org>
(cherry picked from commit 1de23d1fe5d64c8f5e8f24579c0926fabdaace92)

Change-Id: I9384b9632efb5e7a9054b49c6b6f2f4cfc9c9376
Reviewed-on: http://gerrit.openafs.org/5715
Reviewed-by: Derrick Brashear <shadow@dementix.org>
Tested-by: Derrick Brashear <shadow@dementix.org>