Add script to flash boot image to boot1 hwpart

Add the script `flash_bootimg_boot1_librem5-devkit.lst`, which flashes
the full boot image generated by u-boot-builder into the boot1 HW
partition of the eMMC.
4 jobs for add-script-to-flash-bootimg-to-boot1 in 3 minutes and 34 seconds (queued for 3 seconds)
latest
Status Job ID Name Coverage
  Build
passed #25651
librem5
build:deb

00:01:31

passed #25650
librem5
build:docs

00:01:51

 
  Test
passed #25652
librem5
test:download:deb

00:01:17

passed #25653
librem5
test:download:pip

00:01:43