crypto/qat: add weak functions

crypto/qat: add weak functions

This patch adds following weak functions to facilitate conditional
compilation of code for those services:
  -  qat_sym_dev_create
  -  qat_asym_dev_create
  -  qat_comp_dev_create
  -  qat_sym_dev_destroy
  -  qat_asym_dev_destroy
  -  qat_comp_dev_destroy
and removes unused files with empty definitions of above functions.

Signed-off-by: Tomasz Jozwiak <tomaszx.jozwiak@intel.com>
Acked-by: Fiona Trahe <fiona.trahe@intel.com>