board: starqltechn: get board usable - add bootcmd and docs

U-boot is intended to replace linux kernel in android boot image(ABL), and
it's FIT payload to replace initramfs file. The boot process is similar to
boot image with linux:
- android bootloader (ABL) unpacks android boot image
- ABL sets `linux,initrd-start property` in chosen node in unpacked FDT
- ABL sets x0 register to FDT address, and passes control to u-boot
- u-boot reads x0 register, and stores it in `prevbl_fdt_addr` env variable
- u-boot reads `linux,initrd-start` property,
and stores it in `prevbl_initrd_start_addr`

In this way, u-boot bootcmd relies on `prevbl_initrd_start_addr` env
variable, and boils down to `bootm $prevbl_initrd_start_addr`.
If more control on boot process is desired, pack a boot script in
FIT image, and put it to default configuration

What done:
- strip unneeded config options
- add FIT image support
- add framebuffer node, u-boot logo and video console
- increase LMB_MAX_REGIONS, to store all linux dtb reserved memory regions
- add linux kernel image header

Uart driver causes hang, when u-boot is used in android boot image instead
of linux. Temporary disable console driver, until investigated and fixed.

Signed-off-by: Dzmitry Sankouski <dsankouski@gmail.com>
Cc: Ramon Fried <rfried.dev@gmail.com>
diff --git a/configs/starqltechn_defconfig b/configs/starqltechn_defconfig
index f57bb85..75e8409 100644
--- a/configs/starqltechn_defconfig
+++ b/configs/starqltechn_defconfig
@@ -2,16 +2,18 @@
 CONFIG_SKIP_LOWLEVEL_INIT=y
 CONFIG_POSITION_INDEPENDENT=y
 CONFIG_ARCH_SNAPDRAGON=y
-CONFIG_SYS_TEXT_BASE=0x80000000
-CONFIG_SYS_MALLOC_LEN=0x81f000
 CONFIG_DEFAULT_DEVICE_TREE="starqltechn"
+CONFIG_BOOTDELAY=0
+CONFIG_FIT=y
+CONFIG_FIT_VERBOSE=y
 CONFIG_TARGET_STARQLTECHN=y
 CONFIG_IDENT_STRING="\nSamsung S9 SM-G9600"
 CONFIG_SYS_LOAD_ADDR=0x80000000
-CONFIG_USE_PREBOOT=y
+CONFIG_LMB_MAX_REGIONS=64
 # CONFIG_DISPLAY_CPUINFO is not set
 CONFIG_HUSH_PARSER=y
 CONFIG_CMD_GPIO=y
+# CONFIG_REQUIRE_SERIAL_CONSOLE is not set
 # CONFIG_NET is not set
 # CONFIG_DM_STDIO is not set
 CONFIG_CLK=y
@@ -20,5 +22,16 @@
 CONFIG_PINCTRL=y
 CONFIG_DM_PMIC=y
 CONFIG_PMIC_PM8916=y
-CONFIG_MSM_GENI_SERIAL=y
+# CONFIG_MSM_GENI_SERIAL is not set
 CONFIG_SPMI_MSM=y
+CONFIG_LINUX_KERNEL_IMAGE_HEADER=y
+CONFIG_SAVE_PREV_BL_INITRAMFS_START_ADDR=y
+CONFIG_SAVE_PREV_BL_FDT_ADDR=y
+CONFIG_DM_VIDEO=y
+CONFIG_VIDEO_LOGO=y
+CONFIG_CMD_VIDCONSOLE=y
+CONFIG_CONSOLE_NORMAL=y
+CONFIG_SYS_WHITE_ON_BLACK=y
+CONFIG_VIDEO_DT_SIMPLEFB=y
+CONFIG_VIDEO_SIMPLE=y
+CONFIG_CMD_BMP=y