net/bnxt: fix device init error path

1. bnxt_dev_init() invokes bnxt_dev_uninit() on failure. So there is
   no need to do individual function cleanups in failure path.
2. rearrange the check for primary process to remove an unwanted goto.
3. fix to invoke bnxt_hwrm_func_buf_unrgtr() in bnxt_dev_uninit() when
   it is needed.

Fixes: b7778e8a1c00 ("net/bnxt: refactor to properly allocate resources for PF/VF")
Cc: stable@dpdk.org
Signed-off-by: Kalesh AP <kalesh-anakkur.purayil@broadcom.com>
Reviewed-by: Somnath Kotur <somnath.kotur@broadcom.com>