soc/mediatek/common: Increase WAIT_AUX_READY_TIME_MS

Increase WAIT_AUX_READY_TIME_MS from 1 ms to 3 ms fix a 20s timeout bug
on Google/Cherry/Tomato and possibly other MediaTek Chromebooks
introduced in commit 6ba2df9be5 (soc/mediatek/common: Use polling to
reduce eDP HPD wait time).

Change-Id: I6f41c3733e67c85e4aea3ce3b641a98cad94715c
Signed-off-by: Ingo Reitz <9l@9lo.re>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/88991
Reviewed-by: Yidi Lin <yidilin@google.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Yu-Ping Wu <yupingso@google.com>
Reviewed-by: Paul Menzel <paulepanter@mailbox.org>

src/soc/mediatek/common/dp/include/soc/dptx_common.h

@@ -70,7 +70,7 @@
 #define MAX_LANECOUNT				4
 
 #define HPD_WAIT_TIMEOUT_MS			200
-#define WAIT_AUX_READY_TIME_MS			1
+#define WAIT_AUX_READY_TIME_MS			3
 
 enum {
 	DP_LANECOUNT_1	= 0x1,