lang/rust: Update to 1.45.0
- This Rust release comes with LLVM 10. Drop the LLVM patches we no longer need.
- On FreeBSD 13.0 powerpc64 set the elfv2 ABI explicitly in the Rust target instead of patching LLVM.
- Build LLVM with Ninja. It can shorten the build time slightly.
- Force rebuild all consumers to catch regressions early
Changes: https://blog.rust-lang.org/2020/07/16/Rust-1.45.0.html
Tested by: mikael, pkubaj, tobik
With hat: rust
Differential Revision: https://reviews.freebsd.org/D25658