Error log had been collected if PDU ref count went negative. However,
error log is not easy to notice. SPDK iSCSI target is more stable
than before and SPDK iSCSI task has such assert. Hence replace
error log by assert for PDU.
Signed-off-by: Shuhei Matsumoto <shuhei.matsumoto.xt@hitachi.com>
Change-Id: I28c4f5e29f0dfd72436b0131e09f9707822165fc
Reviewed-on: https://review.gerrithub.io/c/spdk/spdk/+/477630
Tested-by: SPDK CI Jenkins <sys_sgci@intel.com>
Reviewed-by: Jim Harris <james.r.harris@intel.com>
Reviewed-by: Changpeng Liu <changpeng.liu@intel.com>
83bcd693b0