exportfs: Change bcachefs fid_type enum to avoid conflicts

Per Amir Goldstein, the fid types that bcachefs picked conflicted with
xfs and fuse, which previously were in use but not deviced in the master
enum.

Since bcachefs is still out of tree, we can move.

https://lore.kernel.org/linux-next/20231026203733.fx65mjyic4pka3e5@moria.home.lan/T/#ma59f65ba61f605b593e69f4690dbd317526d83baSigned-off-by: Kent Overstreet <kent.overstreet@linux.dev>

include/linux/exportfs.h

@@ -98,18 +98,18 @@ enum fid_type {
 	 */
 	FILEID_FAT_WITH_PARENT = 0x72,
 
-	/*
-	 * 64 bit inode number, 32 bit subvolume, 32 bit generation number:
-	 */
-	FILEID_BCACHEFS_WITHOUT_PARENT = 0x80,
-	FILEID_BCACHEFS_WITH_PARENT = 0x81,
-
 	/*
 	 * 128 bit child FID (struct lu_fid)
 	 * 128 bit parent FID (struct lu_fid)
 	 */
 	FILEID_LUSTRE = 0x97,
 
+	/*
+	 * 64 bit inode number, 32 bit subvolume, 32 bit generation number:
+	 */
+	FILEID_BCACHEFS_WITHOUT_PARENT = 0xb1,
+	FILEID_BCACHEFS_WITH_PARENT = 0xb2,
+
 	/*
 	 * 64 bit unique kernfs id
 	 */