debian: move ceph_argparse into ceph-common

debian: move ceph_argparse into ceph-common

Prior to this commit, if a user installed the "ceph-common" Debian
package without installing "ceph", then /usr/bin/ceph would crash
because it was missing the ceph_argparse library.

Ship the ceph_argparse library in "ceph-common" instead of "ceph". (This
was the intention of the original commit that moved argparse to "ceph",
2a23eac54957e596d99985bb9e187a668251a9ec)

http://tracker.ceph.com/issues/11388 Refs: #11388

Reported-by: Jens Rosenboom <j.rosenboom@x-ion.de>
Signed-off-by: Ken Dreyer <kdreyer@redhat.com>