Use SPDX license format and update packed_simd crate link (#1297)

Author: atouchet

Diff for: README.md

@@ -15,4 +15,4 @@ This repository contains two main crates:
   standard library run-time CPU feature detection.
 
 The `std::simd` component now lives in the
-[`packed_simd`](https://github.com/rust-lang-nursery/packed_simd) crate.
+[`packed_simd_2`](https://github.com/rust-lang/packed_simd) crate.

Diff for: crates/core_arch/Cargo.toml

@@ -12,7 +12,7 @@ repository = "https://github.com/rust-lang/stdarch"
 readme = "README.md"
 keywords = ["core", "simd", "arch", "intrinsics"]
 categories = ["hardware-support", "no-std"]
-license = "MIT/Apache-2.0"
+license = "MIT OR Apache-2.0"
 build = "build.rs"
 edition = "2018"
 

Diff for: crates/std_detect/Cargo.toml

@@ -12,7 +12,7 @@ repository = "https://github.com/rust-lang/stdarch"
 readme = "README.md"
 keywords = ["std", "run-time", "feature", "detection"]
 categories = ["hardware-support"]
-license = "MIT/Apache-2.0"
+license = "MIT OR Apache-2.0"
 edition = "2018"
 
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