ntfs3: transition magic number to shared constant

Use the common FSLABEL_MAX constant instead of a hardcoded magic
constant of 256.

Signed-off-by: Ethan Ferguson <ethan.ferguson@zetier.com>
Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>

Author: ethan-ferguson-zetier

fs/ntfs3/ntfs_fs.h

@@ -280,7 +280,7 @@ struct ntfs_sb_info {
 		__le16 flags; // Cached current VOLUME_INFO::flags, VOLUME_FLAG_DIRTY.
 		u8 major_ver;
 		u8 minor_ver;
-		char label[256];
+		char label[FSLABEL_MAX];
 		bool real_dirty; // Real fs state.
 	} volume;