iscsi-target: Move sendtargets parsing into iscsit_process_text_cmd

This patch moves ISCSI_OP_TEXT PDU buffer sanity checks to
iscsit_process_text_cmd() code, so that it can be shared
with iser-target code.

It adds IFC_SENDTARGETS_ALL + iscsi_cmd->text_in_ptr in order
to save text payload for ISCSI_OP_TEXT_RSP, and updates
iscsit_release_cmd() to assigned memory.

Cc: Or Gerlitz <ogerlitz@mellanox.com>
Cc: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
diff --git a/drivers/target/iscsi/iscsi_target_util.c b/drivers/target/iscsi/iscsi_target_util.c
index 08a3bac..fe712d6 100644
--- a/drivers/target/iscsi/iscsi_target_util.c
+++ b/drivers/target/iscsi/iscsi_target_util.c
@@ -681,6 +681,7 @@
 	kfree(cmd->seq_list);
 	kfree(cmd->tmr_req);
 	kfree(cmd->iov_data);
+	kfree(cmd->text_in_ptr);
 
 	kmem_cache_free(lio_cmd_cache, cmd);
 }