LU-1199 build: fix for configure args with space inside

LU-1199 build: fix for configure args with space inside

Fix passing arguments with space inside to configure script.
The following example demostrate this issue:
  sh ./autogen.sh
  CFLAGS=" -g -O2 -Werror" ./configure
  make rpms
configure: error: unrecognized option: -g
Try `./configure --help' for more information.
error: Bad exit status from /var/tmp/rpm-tmp.M5V8zv (%build)
RPM build errors:
    Bad exit status from /var/tmp/rpm-tmp.M5V8zv (%build)
make[1]: *** [rpms-real] Error 1
make: *** [rpms] Error 2

Signed-off-by: Dmitry Eremin <dmitry.eremin@intel.com>
Change-Id: I65fab13d8ef97f0c48a159d77500b66253947aa9
Reviewed-on: http://review.whamcloud.com/7574
Tested-by: Hudson
Tested-by: Maloo <whamcloud.maloo@gmail.com>
Reviewed-by: Minh Diep <minh.diep@intel.com>
Reviewed-by: Bob Glossman <bob.glossman@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>