meson64: bump u-boot to 2021.07 // HC4/N2(+) cleanups (#3155)

* meson64: bump u-boot to 2021.07, rework patches

- as always based on chewitt's tree, with differences:
  - squashed versions of HC4+SATA, Radxa Zero, DT tree sync patches
    - so that DTB/config/code changes related to the same feature/board are grouped
  - removed documentation changes and Makefile reordering patches

Signed-off-by: Ricardo Pardini <ricardo@pardini.net>

* meson64: ODROID HC4/N2: simplify/remove board vs family hacks; better SPI support

- thanks to mainline 2021.07 u-boot and it's HC4 config we can remove the conditionals
- boards now define the u-boot vars instead of conditionals in family
- on the HC4, build u-boot twice: one for SD (old C4 config) and one for HC4 (new SATA/SPI config)
  - reason is that the HC4 version does not work very well unless it is actually booted from SPI
- meson64_common: don't override UBOOT_TARGET_MAP if board-defined
  - but the default UBOOT_TARGET_MAP is still defined if the board didn't
- (sneakily) add lm-sensors fancontrol to the HC4's board packages

Signed-off-by: Ricardo Pardini <ricardo@pardini.net>

config/sources/families/meson-sm1.conf

@@ -6,28 +6,7 @@ GOVERNOR=ondemand
 
 [[ ${BRANCH} == legacy ]] && SERIALCON=ttyS0
 
-if [[ ${BRANCH} == edge ]] && [[ $BOARD == odroidhc4 ]]; then
-	# Experimental, use chewitt's u-boot, which enables SPI+SATA booting.
-	display_alert "Using experimental u-boot with SPI+SATA" "edge+odroidhc4" "info"
-	BOOTSOURCE="https://github.com/chewitt/u-boot.git"
-	BOOTDIR='u-boot-chewitt'
-	BOOTBRANCH='branch:amlogic-2021.07'
-	UBOOT_TARGET_MAP="u-boot-dtb.img;;u-boot.bin.sd.bin:u-boot.bin u-boot-dtb.img u-boot.bin:u-boot-spi.bin"
-	BOOTCONFIG="odroid-hc4_defconfig" # hc4_defconfig vs c4_defconfig, enables PCIe+SATA stuff.
-
-	write_uboot_platform_mtd() {
-		if [[ -f $1/u-boot-spi.bin ]]; then
-			dd if=$1/u-boot-spi.bin of=/dev/mtdblock0
-			sync
-		else
-			echo "SPI u-boot image not found!"
-			exit 1
-		fi
-	}
-fi
-
-family_tweaks()
-{
+family_tweaks() {
 	:
 }