[MIPS] Alchemy: Get rid of au_ffs().

It was plain a bad idea ...
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

arch/mips/au1000/common/dbdma.c

@@ -859,7 +859,7 @@ dbdma_interrupt(int irq, void *dev_id)
 
 	intstat = dbdma_gptr->ddma_intstat;
 	au_sync();
-	chan_index = au_ffs(intstat) - 1;
+	chan_index = ffs(intstat);
 
 	ctp = chan_tab_ptr[chan_index];
 	cp = ctp->chan_ptr;

arch/mips/au1000/common/irq.c

@@ -481,7 +481,7 @@ static void intc0_req0_irqdispatch(void)
 		return;
 	}
 #endif
-	irq = au_ffs(intc0_req0) - 1;
+	irq = ffs(intc0_req0);
 	intc0_req0 &= ~(1 << irq);
 	do_IRQ(irq);
 }
@@ -497,7 +497,7 @@ static void intc0_req1_irqdispatch(void)
 	if (!intc0_req1)
 		return;
 
-	irq = au_ffs(intc0_req1) - 1;
+	irq = ffs(intc0_req1);
 	intc0_req1 &= ~(1 << irq);
 	do_IRQ(irq);
 }
@@ -517,7 +517,7 @@ static void intc1_req0_irqdispatch(void)
 	if (!intc1_req0)
 		return;
 
-	irq = au_ffs(intc1_req0) - 1;
+	irq = ffs(intc1_req0);
 	intc1_req0 &= ~(1 << irq);
 	irq += 32;
 	do_IRQ(irq);
@@ -534,7 +534,7 @@ static void intc1_req1_irqdispatch(void)
 	if (!intc1_req1)
 		return;
 
-	irq = au_ffs(intc1_req1) - 1;
+	irq = ffs(intc1_req1);
 	intc1_req1 &= ~(1 << irq);
 	irq += 32;
 	do_IRQ(irq);

arch/mips/au1000/pb1200/irqmap.c

@@ -74,7 +74,7 @@ irqreturn_t pb1200_cascade_handler( int irq, void *dev_id)
 	bcsr->int_status = bisr;
 	for( ; bisr; bisr &= (bisr-1) )
 	{
-		extirq_nr = (PB1200_INT_BEGIN-1) + au_ffs(bisr);
+		extirq_nr = PB1200_INT_BEGIN + au_ffs(bisr);
 		/* Ack and dispatch IRQ */
 		do_IRQ(extirq_nr);
 	}

include/asm-mips/mach-au1x00/au1000.h

@@ -98,16 +98,6 @@ static __inline__ int au_ffz(unsigned int x)
 	return __ilog2(x & -x);
 }
 
-/*
- * ffs: find first bit set. This is defined the same way as
- * the libc and compiler builtin ffs routines, therefore
- * differs in spirit from the above ffz (man ffs).
- */
-static __inline__ int au_ffs(int x)
-{
-	return __ilog2(x & -x) + 1;
-}
-
 /* arch/mips/au1000/common/clocks.c */
 extern void set_au1x00_speed(unsigned int new_freq);
 extern unsigned int get_au1x00_speed(void);