storage: Remove unused attribute conn from 'checkPool' callback

In order to be able to use 'checkPool' inside functions which do not
have any connection reference, 'conn' attribute needs to be discarded
from the checkPool's signature, since it's not used by any storage backend
anyway.

src/storage/storage_backend.h

@@ -34,8 +34,7 @@
 typedef char * (*virStorageBackendFindPoolSources)(virConnectPtr conn,
                                                    const char *srcSpec,
                                                    unsigned int flags);
-typedef int (*virStorageBackendCheckPool)(virConnectPtr conn,
-                                          virStoragePoolObjPtr pool,
+typedef int (*virStorageBackendCheckPool)(virStoragePoolObjPtr pool,
                                           bool *active);
 typedef int (*virStorageBackendStartPool)(virConnectPtr conn,
                                           virStoragePoolObjPtr pool);

src/storage/storage_backend_fs.c

@@ -533,8 +533,7 @@ virStorageBackendFileSystemUnmount(virStoragePoolObjPtr pool)
 
 
 static int
-virStorageBackendFileSystemCheck(virConnectPtr conn ATTRIBUTE_UNUSED,
-                                 virStoragePoolObjPtr pool,
+virStorageBackendFileSystemCheck(virStoragePoolObjPtr pool,
                                  bool *isActive)
 {
     if (pool->def->type == VIR_STORAGE_POOL_DIR) {

src/storage/storage_backend_iscsi.c

@@ -236,8 +236,7 @@ virStorageBackendISCSIFindPoolSources(virConnectPtr conn ATTRIBUTE_UNUSED,
 }
 
 static int
-virStorageBackendISCSICheckPool(virConnectPtr conn ATTRIBUTE_UNUSED,
-                                virStoragePoolObjPtr pool,
+virStorageBackendISCSICheckPool(virStoragePoolObjPtr pool,
                                 bool *isActive)
 {
     char *session = NULL;

src/storage/storage_backend_logical.c

@@ -479,8 +479,7 @@ virStorageBackendLogicalFindPoolSources(virConnectPtr conn ATTRIBUTE_UNUSED,
 
 
 static int
-virStorageBackendLogicalCheckPool(virConnectPtr conn ATTRIBUTE_UNUSED,
-                                  virStoragePoolObjPtr pool,
+virStorageBackendLogicalCheckPool(virStoragePoolObjPtr pool,
                                   bool *isActive)
 {
     *isActive = virFileExists(pool->def->target.path);

src/storage/storage_backend_mpath.c

@@ -245,8 +245,7 @@ virStorageBackendGetMaps(virStoragePoolObjPtr pool)
 }
 
 static int
-virStorageBackendMpathCheckPool(virConnectPtr conn ATTRIBUTE_UNUSED,
-                                virStoragePoolObjPtr pool ATTRIBUTE_UNUSED,
+virStorageBackendMpathCheckPool(virStoragePoolObjPtr pool ATTRIBUTE_UNUSED,
                                 bool *isActive)
 {
     *isActive = virFileExists("/dev/mpath");

src/storage/storage_backend_scsi.c

@@ -844,8 +844,7 @@ deleteVport(virConnectPtr conn,
 
 
 static int
-virStorageBackendSCSICheckPool(virConnectPtr conn ATTRIBUTE_UNUSED,
-                               virStoragePoolObjPtr pool,
+virStorageBackendSCSICheckPool(virStoragePoolObjPtr pool,
                                bool *isActive)
 {
     char *path = NULL;

src/storage/storage_backend_zfs.c

@@ -41,8 +41,7 @@ VIR_LOG_INIT("storage.storage_backend_zfs");
 
 
 static int
-virStorageBackendZFSCheckPool(virConnectPtr conn ATTRIBUTE_UNUSED,
-                              virStoragePoolObjPtr pool ATTRIBUTE_UNUSED,
+virStorageBackendZFSCheckPool(virStoragePoolObjPtr pool ATTRIBUTE_UNUSED,
                               bool *isActive)
 {
     char *devpath;

src/storage/storage_driver.c

@@ -100,7 +100,7 @@ storageDriverAutostart(void)
         }
 
         if (backend->checkPool &&
-            backend->checkPool(conn, pool, &started) < 0) {
+            backend->checkPool(pool, &started) < 0) {
             virErrorPtr err = virGetLastError();
             VIR_ERROR(_("Failed to initialize storage pool '%s': %s"),
                       pool->def->name, err ? err->message :