mtd: pmc551: fix signedness bug in init_pmc551()

Since "length" is a u32, the error handling below didn't work when
fixup_pmc551() returns -ENODEV.

	if ((length = fixup_pmc551(PCI_Device)) <= 0)

This patch changes both the type of "length" and the return type of
fixup_pmc551() to int.
Signed-off-by: Xi Wang <xi.wang@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

drivers/mtd/devices/pmc551.c

@@ -359,7 +359,7 @@ static int pmc551_write(struct mtd_info *mtd, loff_t to, size_t len,
  * mechanism
  * returns the size of the memory region found.
  */
-static u32 fixup_pmc551(struct pci_dev *dev)
+static int fixup_pmc551(struct pci_dev *dev)
 {
 #ifdef CONFIG_MTD_PMC551_BUGFIX
 	u32 dram_data;
@@ -669,7 +669,7 @@ static int __init init_pmc551(void)
 	struct mypriv *priv;
 	int found = 0;
 	struct mtd_info *mtd;
-	u32 length = 0;
+	int length = 0;
 
 	if (msize) {
 		msize = (1 << (ffs(msize) - 1)) << 20;