Outdated data layout

[mkroening]

When building with make release=1, one gets:

warning: Linking two modules of different data layouts: '' is 'e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128' whereas 'rusty_loader.7uo39jl7-cgu.0' is 'e-m:e-i64:64-f80:128-n8:16:32:64-S128'

rust-lang/rust@8b19922 updated the data layouts to include new X86 address spaces in preparation for LLVM 10 rust-lang/rust#67900.

I think, it would be best to update our data layouts. I'll prepare PRs.