fix(bzip2-sys): license expression to be a valid spdx expression

see: #144

Author: snoweuph

bzip2-sys/Cargo.toml

@@ -4,7 +4,7 @@ version = "0.1.13+1.0.8"
 authors = ["Alex Crichton <alex@alexcrichton.com>"]
 links = "bzip2"
 build = "build.rs"
-license = "MIT/Apache-2.0"
+license = "MIT OR Apache-2.0"
 repository = "https://github.com/alexcrichton/bzip2-rs"
 homepage = "https://github.com/alexcrichton/bzip2-rs"
 documentation = "https://docs.rs/bzip2-sys"