drm/radeon/dp: bump i2c-over-aux retries to 7

As per the DP1.2 spec.  Noticed while reviewing
Thierry's drm/dp patches. Also bump native aux
retries to 7 for consistency.

Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/radeon/atombios_dp.c

@@ -161,7 +161,7 @@ static int radeon_dp_aux_native_write(struct radeon_connector *radeon_connector,
 	msg[3] = (msg_bytes << 4) | (send_bytes - 1);
 	memcpy(&msg[4], send, send_bytes);
 
-	for (retry = 0; retry < 4; retry++) {
+	for (retry = 0; retry < 7; retry++) {
 		ret = radeon_process_aux_ch(dig_connector->dp_i2c_bus,
 					    msg, msg_bytes, NULL, 0, delay, &ack);
 		if (ret == -EBUSY)
@@ -195,7 +195,7 @@ static int radeon_dp_aux_native_read(struct radeon_connector *radeon_connector,
 	msg[2] = DP_AUX_NATIVE_READ << 4;
 	msg[3] = (msg_bytes << 4) | (recv_bytes - 1);
 
-	for (retry = 0; retry < 4; retry++) {
+	for (retry = 0; retry < 7; retry++) {
 		ret = radeon_process_aux_ch(dig_connector->dp_i2c_bus,
 					    msg, msg_bytes, recv, recv_bytes, delay, &ack);
 		if (ret == -EBUSY)
@@ -274,7 +274,7 @@ int radeon_dp_i2c_aux_ch(struct i2c_adapter *adapter, int mode,
 		break;
 	}
 
-	for (retry = 0; retry < 4; retry++) {
+	for (retry = 0; retry < 7; retry++) {
 		ret = radeon_process_aux_ch(auxch,
 					    msg, msg_bytes, reply, reply_bytes, 0, &ack);
 		if (ret == -EBUSY)