PinePhone: support crust firmware to improve battery time

Long-term:

• Contact maintainer of gcc-cross-embedded in Alpine and ask if we can add or1k-elf and move gcc-cross-embedded and binutils-cross-embedded to community instead of testing.
  • this should be done ASAP.
• Upstream crust-firmware package that builds with gcc-cross-embedded to Alpine
• When it's all in Alpine stable, we can use that

Short-term: Based on the work in !1163 (merged):

• Make pmbootstrap aportgen binutils-or1k possible (needs minor adjustments in pmbootstrap code, see output from the MR)
• Make pmbootstrap aportgen gcc-or1k-embedded possible (needs minor adjustments too, in contrary to existing gcc-armv7 etc. packages, this does not build against musl libc, but against newlib; therefore I'd add something like the -embedded suffix)
  • This appears to run into a timeout every other time it is built? Not sure if we can fix that, or if we just have to do multiple tries until it builds properly :\
• Review pmbootstrap!1920 (merged) and get it merged, so we can use pmb:cross-native with the firmware package
• Make sure that the curst firmware can be built with the two above
• Put the generated pmaports into pmaports.git; create separate MRs for:
  • binutils-or1k
  • gcc-or1k-embedded
  • the firmware pkg and uboot update
• Update monitoring so we make sure to update the gcc and binutils versions after new versions of the upstream packages are released