drivers/i2c/ptn3460: Provide chip driver for PTN3460

This patch provides a chip driver for the DP-2-LVDS bridge PTN3460.
The bridge is configured via I2C. As the mainboard has all the
information regarding the attached LCD type, there are three hooks into
mainboard code to get the information like EDID data and PTN config.

TEST=Display is working on Siemens mainboards (e.g. mc_tcu3, mc_apl1, ...).

Change-Id: Ie4c8176cd16836fa5b8fd2f72faf7a55723b82f6
Signed-off-by: Uwe Poeche <uwe.poeche@siemens.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/36642
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Werner Zeh <werner.zeh@siemens.com>
diff --git a/src/drivers/i2c/ptn3460/chip.h b/src/drivers/i2c/ptn3460/chip.h
new file mode 100644
index 0000000..8bd6d9e
--- /dev/null
+++ b/src/drivers/i2c/ptn3460/chip.h
@@ -0,0 +1,3 @@
+struct drivers_i2c_ptn3460_config {
+
+};