The default gcc version for pkgsCross.avr.buildPackages is 10.x, which
seems to be able to build the layout derivation just fine.
Change-Id: Ib7790419f38121ea2b1a09c790ef3a04afc0f9f8
Reviewed-on: https://cl.tvl.fyi/c/depot/+/3712
Tested-by: BuildkiteCI
Reviewed-by: grfn <grfn@gws.fyi>