ARM: clps711x: Set PLL clock to zero if we work from 13 mHz source

This clock will be used in audio subsystem. Since audio cannot work
without PLL we should indicate this.
Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Signed-off-by: Olof Johansson <olof@lixom.net>

arch/arm/mach-clps711x/common.c

@@ -301,6 +301,7 @@ void __init clps711x_timer_init(void)
 		cpu = ext;
 		bus = cpu;
 		spi = 135400;
+		pll = 0;
 	} else {
 		cpu = pll;
 		if (cpu >= 36864000)