imx8: Make it possible to use the DP instead of the HDMI firmware

arch/arm/mach-imx/imx8m/Kconfig

@@ -12,6 +12,10 @@ config IMX8MQ
 	bool
 	select IMX8M
 
+config IMX8MQ_DP
+	depends on IM8MQ
+	bool "Use iMX8MQ Display Port firmware"
+
 config IMX8MM
 	bool
 	select IMX8M
@@ -61,6 +65,7 @@ config TARGET_LIBREM5
 	bool "Purism Librem5 Phone"
 	select IMX8MQ
 	select IMX8M_LPDDR4
+	select IMX8MQ_DP
 
 config TARGET_LIBREM5_DEVKIT
 	bool "Purism Librem5 devkit board"

arch/arm/mach-imx/imx8m/imximage.cfg

@@ -8,7 +8,13 @@
 FIT
 BOOT_FROM	sd
 #ifdef CONFIG_IMX8MQ
-SIGNED_HDMI	signed_hdmi_imx8m.bin
+# ifdef CONFIG_IMX8MQ_DP
+#   warning "Using DP Firmware"
+signed_hdmi	signed_dp_imx8m.bin
+# else
+#   warning "Using HDMI Firmware"
+signed_hdmi	signed_hdmi_imx8m.bin
+# endif
 #endif
 LOADER		spl/u-boot-spl-ddr.bin	0x7E1000
 SECOND_LOADER	u-boot.itb		0x40200000 0x60000