board: qualcomm: Add support for dragonboard845c

Add support for 96Boards Dragonboard 845C aka Robotics RB3 development
platform. This board complies with 96Boards Open Platform Specifications.

Features:
- Qualcomm Snapdragon SDA845 SoC
- 4GiB RAM
- 64GiB UFS drive

U-boot is chain loaded by ABL in 64-bit mode as part of boot.img.
For detailed build and boot instructions, refer to
doc/board/qualcomm/sdm845.rst, board: dragonboard845c.

Signed-off-by: Sumit Garg <sumit.garg@linaro.org>
Reviewed-by: Ramon Fried <rfried.dev@gmail.com>

include/configs/dragonboard845c.h

@@ -0,0 +1,21 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Configuration file for Dragonboard 845c, based on Qualcomm SDA845 chip
+ *
+ * (C) Copyright 2022 Sumit Garg <sumit.garg@linaro.org>
+ */
+
+#ifndef __CONFIGS_SDM845_H
+#define __CONFIGS_SDM845_H
+
+#include <linux/sizes.h>
+#include <asm/arch/sysmap-sdm845.h>
+
+#define CONFIG_SYS_BAUDRATE_TABLE	{ 115200, 230400, 460800, 921600 }
+
+#define CONFIG_EXTRA_ENV_SETTINGS \
+	"bootm_size=0x5000000\0"	\
+	"bootm_low=0x80000000\0"	\
+	"bootcmd=bootm $prevbl_initrd_start_addr\0"
+
+#endif