intel raminit: check correct registers in channel_test

Found while doing code review. No actual problem was observed.

Test system:
* Intel IvyBridge
* Gigabyte GA-B75M-D3H

Verify byte-lane error count registers 0 to 7 instead of verifying byte-lane
error count register 0 eight times in a row.

Change-Id: Ife6ac6558b2f65ad947870cde5f15d90560ce6d9
Signed-off-by: Patrick Rudolph <siro@das-labor.org>
Reviewed-on: http://review.coreboot.org/10664
Tested-by: build bot (Jenkins)
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>

src/northbridge/intel/sandybridge/raminit_native.c

@@ -3392,7 +3392,7 @@ static void channel_test(ramctr_timing * ctrl)
 		write32(DEFAULT_MCHBAR + 0x4284 + (channel << 10), 0x000c0001);
 		wait_428c(channel);
 		FOR_ALL_LANES
-		    if (read32(DEFAULT_MCHBAR + 0x4340 + (channel << 10)))
+		    if (read32(DEFAULT_MCHBAR + 0x4340 + (channel << 10) + 4 * lane))
 			 die("Mini channel test failed (2)\n");
 	}
 }