mtd: bcm47xxpart: detect "factory" partition

A new type of partition with magic FCTY was found on Huawei E970:
46 43 54 59 4b 51 37 4e  41 42 31 38 41 32 39 30  |FCTYKQ7NAB18A290|
Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>

drivers/mtd/bcm47xxpart.c

@@ -27,6 +27,7 @@
 
 /* Magics */
 #define BOARD_DATA_MAGIC		0x5246504D	/* MPFR */
+#define FACTORY_MAGIC			0x59544346	/* FCTY */
 #define POT_MAGIC1			0x54544f50	/* POTT */
 #define POT_MAGIC2			0x504f		/* OP */
 #define ML_MAGIC1			0x39685a42
@@ -118,6 +119,13 @@ static int bcm47xxpart_parse(struct mtd_info *master,
 			continue;
 		}
 
+		/* Found on Huawei E970 */
+		if (buf[0x000 / 4] == FACTORY_MAGIC) {
+			bcm47xxpart_add_part(&parts[curr_part++], "factory",
+					     offset, MTD_WRITEABLE);
+			continue;
+		}
+
 		/* POT(TOP) */
 		if (buf[0x000 / 4] == POT_MAGIC1 &&
 		    (buf[0x004 / 4] & 0xFFFF) == POT_MAGIC2) {