ARM: at91: drop AT91_TIMER_HZ

Drop AT91_TIMER_HZ as this can be handled using HZ_FIXED. Initial help message
was:

On AT91rm9200 chips where you're using a system clock derived
from the 32768 Hz hardware clock, this tick rate should divide
it exactly: use a power-of-two value, such as 128 or 256, to
reduce timing errors caused by rounding.
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>

arch/arm/Kconfig

@@ -1502,7 +1502,7 @@ config HZ_FIXED
 	int
 	default 200 if ARCH_EBSA110 || ARCH_S3C24XX || \
 		ARCH_S5PV210 || ARCH_EXYNOS4
-	default AT91_TIMER_HZ if ARCH_AT91
+	default 128 if SOC_AT91RM9200
 	default SHMOBILE_TIMER_HZ if ARCH_SHMOBILE_LEGACY
 	default 0
 

arch/arm/mach-at91/Kconfig

@@ -103,22 +103,4 @@ config SOC_SAMA5
 	select SOC_SAM_V7
 	select SRAM if PM
 
-comment "Atmel SoCs Feature Selections"
-
-config AT91_TIMER_HZ
-	int "Kernel HZ (jiffies per second)"
-	range 32 1024
-	depends on ARCH_AT91
-	default "128" if SOC_AT91RM9200
-	default "100"
-	help
-	  On AT91rm9200 chips where you're using a system clock derived
-	  from the 32768 Hz hardware clock, this tick rate should divide
-	  it exactly: use a power-of-two value, such as 128 or 256, to
-	  reduce timing errors caused by rounding.
-
-	  On AT91sam926x chips, or otherwise when using a higher precision
-	  system clock (of at least several MHz), rounding is less of a
-	  problem so it can be safer to use a decimal values like 100.
-
 endif