target: Make helpers non static for EXTENDED_COPY command setup

Both target_alloc_sgl() and transport_generic_map_mem_to_cmd() are
required by EXTENDED_COPY logic when setting up internally dispatched
command descriptors, so go ahead and make both of these non static.

Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Martin Petersen <martin.petersen@oracle.com>
Cc: Chris Mason <chris.mason@fusionio.com>
Cc: Roland Dreier <roland@purestorage.com>
Cc: Zach Brown <zab@redhat.com>
Cc: James Bottomley <JBottomley@Parallels.com>
Cc: Nicholas Bellinger <nab@linux-iscsi.org>
Signed-off-by: Nicholas Bellinger <nab@daterainc.com>
diff --git a/include/target/target_core_backend.h b/include/target/target_core_backend.h
index 77f25e0..5ebe21c 100644
--- a/include/target/target_core_backend.h
+++ b/include/target/target_core_backend.h
@@ -74,6 +74,10 @@
 /* core helpers also used by command snooping in pscsi */
 void	*transport_kmap_data_sg(struct se_cmd *);
 void	transport_kunmap_data_sg(struct se_cmd *);
+/* core helpers also used by xcopy during internal command setup */
+int	target_alloc_sgl(struct scatterlist **, unsigned int *, u32, bool);
+sense_reason_t	transport_generic_map_mem_to_cmd(struct se_cmd *,
+		struct scatterlist *, u32, struct scatterlist *, u32);
 
 void	array_free(void *array, int n);