net/iavf/base: fix command buffer memory leak

net/iavf/base: fix command buffer memory leak

Allocated resources were not freed in the event of failure in
iavf_init_asq function. This patch gracefully handles all failures.

Fixes: e5b2a9e957e7 ("net/avf/base: add base code for avf PMD")
Cc: stable@dpdk.org
Signed-off-by: Pandi Kumar Maharajan <pandi.maharajan@intel.com>
Signed-off-by: Paul M Stillwell Jr <paul.m.stillwell.jr@intel.com>
Signed-off-by: Qi Zhang <qi.z.zhang@intel.com>
Acked-by: Qiming Yang <qiming.yang@intel.com>