Annotated dprintf as printf-like

ZFS loves using %llu for uint64_t, but that requires a cast to not 
be noisy - which is even done in many, though not all, places.
Also a couple places used %u for uint64_t, which were promoted
to %llu. 

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rich Ercolani <rincebrain@gmail.com>
Closes #12233

module/zfs/dnode_sync.c

@@ -59,7 +59,7 @@ dnode_increase_indirection(dnode_t *dn, dmu_tx_t *tx)
 
 	dn->dn_phys->dn_nlevels = new_level;
 	dprintf("os=%p obj=%llu, increase to %d\n", dn->dn_objset,
-	    dn->dn_object, dn->dn_phys->dn_nlevels);
+	    (u_longlong_t)dn->dn_object, dn->dn_phys->dn_nlevels);
 
 	/*
 	 * Lock ordering requires that we hold the children's db_mutexes (by
@@ -136,7 +136,8 @@ free_blocks(dnode_t *dn, blkptr_t *bp, int num, dmu_tx_t *tx)
 	dsl_dataset_t *ds = dn->dn_objset->os_dsl_dataset;
 	uint64_t bytesfreed = 0;
 
-	dprintf("ds=%p obj=%llx num=%d\n", ds, dn->dn_object, num);
+	dprintf("ds=%p obj=%llx num=%d\n", ds, (u_longlong_t)dn->dn_object,
+	    num);
 
 	for (int i = 0; i < num; i++, bp++) {
 		if (BP_IS_HOLE(bp))