Stop using deprecated method SetDebug.

Change-Id: I8a856339355073e8a948fe3424fd24dd3e818fc3

cmd/slothfs-gitilesfs/main.go

diff --git a/cmd/slothfs-gitilesfs/main.go b/cmd/slothfs-gitilesfs/main.go
index 52e2543..3ab86f5 100644
--- a/cmd/slothfs-gitilesfs/main.go
+++ b/cmd/slothfs-gitilesfs/main.go
@@ -74,13 +74,11 @@
 		EntryTimeout:    time.Hour,
 		NegativeTimeout: time.Hour,
 		AttrTimeout:     time.Hour,
+		Debug:           *debug,
 	})
 	if err != nil {
 		log.Fatalf("MountFileSystem: %v", err)
 	}
-	if *debug {
-		server.SetDebug(true)
-	}
 	log.Printf("Started gitiles fs FUSE on %s", mntDir)
 	server.Serve()
 }

cmd/slothfs-manifestfs/main.go

diff --git a/cmd/slothfs-manifestfs/main.go b/cmd/slothfs-manifestfs/main.go
index e0e9c07..4e2cf3b 100644
--- a/cmd/slothfs-manifestfs/main.go
+++ b/cmd/slothfs-manifestfs/main.go
@@ -88,13 +88,11 @@
 		EntryTimeout:    time.Hour,
 		NegativeTimeout: time.Hour,
 		AttrTimeout:     time.Hour,
+		Debug:           *debug,
 	})
 	if err != nil {
 		log.Fatalf("MountFileSystem: %v", err)
 	}
-	if *debug {
-		server.SetDebug(true)
-	}
 	log.Printf("Started gitiles fs FUSE on %s", mntDir)
 	server.Serve()
 }

cmd/slothfs-multifs/main.go

diff --git a/cmd/slothfs-multifs/main.go b/cmd/slothfs-multifs/main.go
index 93dcb20..5c5c442 100644
--- a/cmd/slothfs-multifs/main.go
+++ b/cmd/slothfs-multifs/main.go
@@ -78,13 +78,11 @@
 		EntryTimeout:    time.Hour,
 		NegativeTimeout: time.Hour,
 		AttrTimeout:     time.Hour,
+		Debug:           *debug,
 	})
 	if err != nil {
 		log.Fatalf("MountFileSystem: %v", err)
 	}
-	if *debug {
-		server.SetDebug(true)
-	}
 	log.Printf("Started Git MultiFS FUSE on %s", mntDir)
 	server.Serve()
 }