nitrogen6x: display use I2C detect for HDMI

The HPD pin and RX_SENSE registers have proven to be less reliable
than using I2C on the EDID pins for detection of an HDMI monitor.
In particular, when the HDMI output is reset through a "reboot"
cycle, the detect_hdmi() routine often bounces, resulting in
a failure to detect a connected monitor.

Signed-off-by: Eric Nelson <eric.nelson@boundarydevices.com>
diff --git a/board/boundary/nitrogen6x/nitrogen6x.c b/board/boundary/nitrogen6x/nitrogen6x.c
index a82ec45..2762fcf 100644
--- a/board/boundary/nitrogen6x/nitrogen6x.c
+++ b/board/boundary/nitrogen6x/nitrogen6x.c
@@ -494,10 +494,10 @@
 }
 
 struct display_info_t const displays[] = {{
-	.bus	= -1,
-	.addr	= 0,
+	.bus	= 1,
+	.addr	= 0x50,
 	.pixfmt	= IPU_PIX_FMT_RGB24,
-	.detect	= detect_hdmi,
+	.detect	= detect_i2c,
 	.enable	= do_enable_hdmi,
 	.mode	= {
 		.name           = "HDMI",