clock-imx35: correct arm and ahb clock calculation

According to the Datasheet:
"i.MX35 (MCIMX35) Multimedia Applications Processor Reference Manual,
Rev. 2" "Figure 14-24. Clock Control And Gating"
change the result of get_rate_ahb based on the frequency returned
by get_rate_arm to calculate the proper rate.
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Michael Grzeschik <m.grzeschik@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

arch/arm/mach-mx3/clock-imx35.c

@@ -155,7 +155,7 @@ static unsigned long get_rate_arm(void)
 
 	aad = &clk_consumer[(pdr0 >> 16) & 0xf];
 	if (aad->sel)
-		fref = fref * 2 / 3;
+		fref = fref * 3 / 4;
 
 	return fref / aad->arm;
 }
@@ -164,7 +164,7 @@ static unsigned long get_rate_ahb(struct clk *clk)
 {
 	unsigned long pdr0 = __raw_readl(CCM_BASE + CCM_PDR0);
 	struct arm_ahb_div *aad;
-	unsigned long fref = get_rate_mpll();
+	unsigned long fref = get_rate_arm();
 
 	aad = &clk_consumer[(pdr0 >> 16) & 0xf];