LU-6323 build: fix debian to compile with external IB

LU-6323 build: fix debian to compile with external IB

Debian seems compiling with fixed configurations, if users
want to make debian package with external IB, it won't work.

Signed-off-by: Wang Shilong <wshilong@ddn.com>
Change-Id: I0ecb5c79d5948c0e8ab821c175ca89afee9cb97d
Reviewed-on: http://review.whamcloud.com/13949
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Blake Caldwell <blakec@ornl.gov>
Reviewed-by: Li Xi <lixi@ddn.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>