- add `pre_config_uboot_target` hook for switching BOOTCONFIG across the two targets
- adapt `UBOOT_TARGET_MAP` to not call the defconfig Makefile targets directly, instead, just do a variable assignment (ignored by Make)
- otherwise, when using the defconfig directly in the `UBOOT_TARGET_MAP`, the `post_config_uboot_target` .config changes are overwritten when Make is called
- only patch left is boot usb-nvme-scsi/sata first (still done in meson64.h)
- remove FIP handling from family file `meson-sm1.conf` into board file hook where it belongs
- u-boot: enable more compression methods, EFI debugging, i2c, leds, tcp networking
- use flashcp for mtd writing
- Unchanged:
- confirmed as of v2024.04: using the C4 (not HC4) defconfig is still needed to be able to write to mtd when booted from SD
- also confirmed: one still needs to erase Petitboot using Petitboot, then boot from SD, to be able to flash mainline u-boot to mtd