cpu/via/car: ensure CAR ends up zeroed out

We need to ensure the cache as ram area is set to all zeroes so that
car_migrated works.

Despite a comment claims the previous value is a test pattern it's
actually not used for any testing. Drop the comment too.

Change-Id: I1c91acbca8a860c2ed9c691d08d18718604682d8
Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
Reviewed-on: https://review.coreboot.org/25796
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
diff --git a/src/cpu/via/car/cache_as_ram.inc b/src/cpu/via/car/cache_as_ram.inc
index 2c19453..a131517 100644
--- a/src/cpu/via/car/cache_as_ram.inc
+++ b/src/cpu/via/car/cache_as_ram.inc
@@ -149,12 +149,8 @@
 	movl	%esi, %edi
 	movl	$(CacheSize >> 2), %ecx
-	/*
-	 * 0x5c5c5c5c is a memory test pattern.
-	 * TODO: Check if everything works with the zero pattern as well.
-	 */
-	/* xorl	%eax, %eax */
-	xorl	$0x5c5c5c5c, %eax
+	/* Zero out the cache-as-ram area. */
+	xorl	%eax, %eax
 	rep	stosl
 #ifdef CARTEST