imx-common: timer: clean up

Drop the unneeded code. lib/time.c use timebase_l/h.

Signed-off-by: Peng Fan <peng.fan@nxp.com>
Cc: Stefano Babic <sbabic@denx.de>
Reviewed-by: Stefano Babic <sbabic@denx.de>
diff --git a/arch/arm/imx-common/timer.c b/arch/arm/imx-common/timer.c
index ee6eff2..9b01114 100644
--- a/arch/arm/imx-common/timer.c
+++ b/arch/arm/imx-common/timer.c
@@ -105,9 +105,6 @@
 #endif
 	__raw_writel(i, &cur_gpt->control);
 
-	gd->arch.tbl = __raw_readl(&cur_gpt->counter);
-	gd->arch.tbu = 0;
-
 	return 0;
 }