btrfs: fix some warnings

src/add-ons/kernel/file_systems/btrfs/ExtentAllocator.h

@@ -9,6 +9,8 @@
 #include "Volume.h"
 #include "BTree.h"
 
+#include <DebugSupport.h>
+
 
 //#define TRACE_BTRFS
 #ifdef TRACE_BTRFS
@@ -17,8 +19,6 @@
 #	define TRACE(x...) ;
 #endif
 
-#define ERROR(x...) dprintf("\33[34mbtrfs:\33[0m " x)
-
 
 struct CachedExtent : AVLTreeNode {
 	uint64		offset;

src/add-ons/kernel/file_systems/btrfs/Inode.h

@@ -99,9 +99,9 @@ private:
 };
 
 /*!The Vnode class provides a convenience layer upon get_vnode(), so that
-/* you don't have to call put_vnode() anymore, which may make code more
-/* readable in some cases
-*/
+ * you don't have to call put_vnode() anymore, which may make code more
+ * readable in some cases
+ */
 class Vnode {
 public:
 	Vnode(Volume* volume, ino_t id)

src/add-ons/kernel/file_systems/btrfs/Volume.cpp

@@ -28,7 +28,6 @@
 #else
 #	define TRACE(x...) ;
 #endif
-#	define ERROR(x...) dprintf("\33[34mbtrfs:\33[0m " x)
 
 
 class DeviceOpener {