MIPS: sead3: remove unused cpu_khz variable

This variable seems to have been copied from Malta when SEAD3 support
was introduced, but is likewise unused. Remove it.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Reviewed-by: Markos Chandras <markos.chandras@imgtec.com>
Reviewed-by: James Hogan <james.hogan@imgtec.com>
Signed-off-by: John Crispin <blogic@openwrt.org>
Patchwork: http://patchwork.linux-mips.org/patch/6172/

arch/mips/mti-sead3/sead3-time.c

@@ -13,8 +13,6 @@
 #include <asm/irq.h>
 #include <asm/mips-boards/generic.h>
 
-unsigned long cpu_khz;
-
 static int mips_cpu_timer_irq;
 static int mips_cpu_perf_irq;
 
@@ -109,8 +107,6 @@ void __init plat_time_init(void)
 	pr_debug("CPU frequency %d.%02d MHz\n", (est_freq / 1000000),
 		(est_freq % 1000000) * 100 / 1000000);
 
-	cpu_khz = est_freq / 1000;
-
 	mips_scroll_message();
 
 	plat_perf_setup();