exynos5420: minor correction to CPU frequency print

This divides the CPU frequency by 1,000,000 instead of 2^20.

serial console shows "CPU:   S5P5420 @ 800MHz" instead of
claiming 762MHz.

Change-Id: I70cc5b62f689c5553b57c82be61233fb9f733f6e
Reviewed-on: https://gerrit.chromium.org/gerrit/64743
Reviewed-by: Gabe Black <gabeblack@chromium.org>
Reviewed-by: Ronald G. Minnich <rminnich@chromium.org>
Commit-Queue: David Hendricks <dhendrix@chromium.org>
Tested-by: David Hendricks <dhendrix@chromium.org>
Reviewed-on: http://review.coreboot.org/4434
Tested-by: build bot (Jenkins)
Reviewed-by: Patrick Georgi <patrick@georgi-clan.de>

src/cpu/samsung/exynos5420/cpu.c

@@ -159,7 +159,7 @@ static void cpu_enable(device_t dev)
 static void cpu_init(device_t dev)
 {
 	printk(BIOS_INFO, "CPU:   S5P%X @ %ldMHz\n",
-			cpu_id, get_arm_clk() / (1024*1024));
+			cpu_id, get_arm_clk() / 1000000);
 
 	usb_init(dev);
 }