device-thundercomm-db845c: new device (MR 4047)

Add support for the Qualcomm Robotics (RB3) dev kit, the Thundercomm
DB845c. This is a successor to the arrow 410c board already supported in
postmarketOS. It is based on the SDA845 SoC, almost identical to SDM845
but without a fully featured modem.

All the things you'd expect to work out of the box:
* UART
* USB host and peripheral
* HDMI display out
* Wifi, Bluetooth

device/testing/device-thundercomm-db845c/APKBUILD

+
+# Reference: <https://postmarketos.org/devicepkg>
+# Maintainer: Caleb Connolly <caleb@connolly.tech>
+
+pkgname=device-thundercomm-db845c
+pkgdesc="Thundercomm Dragonboard 845c"
+pkgver=1
+pkgrel=0
+url="https://postmarketos.org"
+license="MIT"
+arch="aarch64"
+options="!check !archcheck"
+depends="
+	linux-postmarketos-qcom-sdm845
+	mkbootimg
+	postmarketos-base
+	postmarketos-update-kernel
+	soc-qcom-sdm845
+	soc-qcom-sdm845-ucm
+	soc-qcom-sdm845-qbootctl
+	fwupd>=1.8.6
+"
+makedepends="devicepkg-dev"
+source="
+	deviceinfo
+"
+subpackages="
+	$pkgname-nonfree-firmware:nonfree_firmware
+"
+
+build() {
+	devicepkg_build $startdir $pkgname
+}
+
+package() {
+	devicepkg_package $startdir $pkgname
+}
+
+nonfree_firmware() {
+	pkgdesc="Modem, GPU and WiFi Firmware"
+	depends="linux-firmware-qcom soc-qcom-sdm845-nonfree-firmware"
+	mkdir "$subpkgdir"
+}
+
+sha512sums="
+832731020692787e954daca9ddff33b2c5e4d66858dc4b78927d290f366101b958d1226b3da8fd5078bb04c3d94b80abe8c4962ce0aa8d60ec8825de49de3207  deviceinfo
+"

device/testing/device-thundercomm-db845c/deviceinfo

+# Reference: <https://postmarketos.org/deviceinfo>
+# Please use double quotes only. You can source this file in shell
+# scripts.
+
+deviceinfo_format_version="0"
+deviceinfo_name="Thundercomm Dragonboard 845c"
+deviceinfo_manufacturer="Thundercomm"
+deviceinfo_codename="thundercomm-db845c"
+deviceinfo_year="2019"
+deviceinfo_arch="aarch64"
+
+# Device related
+deviceinfo_gpu_accelerated="true"
+deviceinfo_mesa_driver="msm"
+deviceinfo_chassis="embedded"
+deviceinfo_keyboard="true"
+deviceinfo_external_storage="true"
+deviceinfo_screen_width="1920"
+deviceinfo_screen_height="1080"
+deviceinfo_no_framebuffer="true"
+
+# Bootloader related
+deviceinfo_flash_method="fastboot"
+deviceinfo_kernel_cmdline="PMOS_NO_OUTPUT_REDIRECT console=ttyMSM0,115200"
+deviceinfo_generate_bootimg="true"
+deviceinfo_bootimg_qcdt="false"
+deviceinfo_bootimg_dtb_second="false"
+deviceinfo_flash_offset_base="0x00000000"
+deviceinfo_flash_offset_kernel="0x00008000"
+deviceinfo_flash_offset_ramdisk="0x01000000"
+deviceinfo_flash_offset_second="0x00f00000"
+deviceinfo_flash_offset_tags="0x00000100"
+deviceinfo_flash_pagesize="4096"
+deviceinfo_flash_sparse="true"
+deviceinfo_flash_fastboot_partition_system="rootfs"
+deviceinfo_getty="ttyMSM0;115200"
+
+# Kernel
+deviceinfo_append_dtb="true"
+deviceinfo_dtb="qcom/sdm845-db845c"
+deviceinfo_flash_kernel_on_update="true"
+
+# Required for devices using UFS as storage (instead of e.g. eMMC)
+deviceinfo_rootfs_image_sector_size="4096"
+
+deviceinfo_modules_initfs="lontium-lt9611"