iscsi-target: Add iSCSI fabric support for target v4.1
The Linux-iSCSI.org target module is a full featured in-kernel software implementation of iSCSI target mode (RFC-3720) for the current WIP mainline target v4.1 infrastructure code for the v3.1 kernel. More information can be found here: http://linux-iscsi.org/wiki/ISCSI This includes support for: * RFC-3720 defined request / response state machines and support for all defined iSCSI operation codes from Section 10.2.1.2 using libiscsi include/scsi/iscsi_proto.h PDU definitions * Target v4.1 compatible control plane using the generic layout in target_core_fabric_configfs.c and fabric dependent attributes within /sys/kernel/config/target/iscsi/ subdirectories. * Target v4.1 compatible iSCSI statistics based on RFC-4544 (iSCSI MIBS) * Support for IPv6 and IPv4 network portals in M:N mapping to TPGs * iSCSI Error Recovery Hierarchy support * Per iSCSI connection RX/TX thread pair scheduling affinity * crc32c + crc32c_intel SSEv4 instruction offload support using libcrypto * CHAP Authentication support using libcrypto * Conversion to use internal SGl allocation with iscsit_alloc_buffs() -> transport_generic_map_mem_to_cmd() (nab: Fix iscsi_proto.h struct scsi_lun usage from linux-next in commit: iscsi: Use struct scsi_lun in iscsi structs instead of u8[8]) (nab: Fix 32-bit compile warnings)