ARM: rename CONFIG_TIMER_CLK_FREQ to COUNTER_FREQUENCY

Many ARMv8 boards define a constant COUNTER_FREQUENCY to specify the
frequency of the ARM Generic Timer (aka. arch timer).
ARMv7 boards traditionally used CONFIG_TIMER_CLK_FREQ for the same
purpose. It seems useful to unify them.
Since there are less occurences of the latter version, lets convert all
users over to COUNTER_FREQUENCY.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Jagan Teki <jagan@openedev.com>
diff --git a/include/configs/mx7_common.h b/include/configs/mx7_common.h
index 5bf8ad7..e2b05ca 100644
--- a/include/configs/mx7_common.h
+++ b/include/configs/mx7_common.h
@@ -21,7 +21,7 @@
 #define CONFIG_MXC_GPT_HCLK
 #define CONFIG_SYSCOUNTER_TIMER
 #define CONFIG_SC_TIMER_CLK 8000000 /* 8Mhz */
-#define CONFIG_TIMER_CLK_FREQ CONFIG_SC_TIMER_CLK
+#define COUNTER_FREQUENCY CONFIG_SC_TIMER_CLK
 #define CONFIG_SYS_FSL_CLK
 
 #define CONFIG_SYS_BOOTM_LEN	0x1000000