drivers: target: Move prototype declaration of function to header file target_core_pr.h

Move prototype declaration of function
spc_parse_naa_6h_vendor_specific() from target_core_xcopy.c to header
file target_core_pr.h because it is used by more than one file.

This eliminates the following warning in target_core_spc.c:
drivers/target/target_core_spc.c:138:6: warning: no previous prototype for ‘spc_parse_naa_6h_vendor_specific’ [-Wmissing-prototypes]
Signed-off-by: Rashika Kheria <rashika.kheria@gmail.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

drivers/target/target_core_pr.h

@@ -43,6 +43,11 @@
 #define PR_APTPL_MAX_IPORT_LEN			256
 #define PR_APTPL_MAX_TPORT_LEN			256
 
+/*
+ *  Function defined in target_core_spc.c
+ */
+void spc_parse_naa_6h_vendor_specific(struct se_device *, unsigned char *);
+
 extern struct kmem_cache *t10_pr_reg_cache;
 
 extern void core_pr_dump_initiator_port(struct t10_pr_registration *,

drivers/target/target_core_xcopy.c

@@ -39,10 +39,6 @@
 #include "target_core_xcopy.h"
 
 static struct workqueue_struct *xcopy_wq = NULL;
-/*
- * From target_core_spc.c
- */
-extern void spc_parse_naa_6h_vendor_specific(struct se_device *, unsigned char *);
 /*
  * From target_core_device.c
  */