MIPS: RB532: Fix set_latch_u5()

The data to be written is just a byte, so use writeb instead of writel.
Also, dev3.base contains the address, not the data so referencing here
is wrong.
Signed-off-by: NPhil Sutter <n0-1@freewrt.org>
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

arch/mips/rb532/gpio.c

@@ -93,7 +93,7 @@ void set_latch_u5(unsigned char or_mask, unsigned char nand_mask)
 	spin_lock_irqsave(&dev3.lock, flags);
 
 	dev3.state = (dev3.state | or_mask) & ~nand_mask;
-	writel(dev3.state, &dev3.base);
+	writeb(dev3.state, dev3.base);
 
 	spin_unlock_irqrestore(&dev3.lock, flags);
 }