Bump the version to 3.5.4 (#274)

This version includes sparc64-unknown-linux-gnu support

Author: thejpster

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "openssl-src"
-version = "300.5.3+3.5.4"
+version = "300.5.4+3.5.4"
 authors = ["Alex Crichton <[email protected]>"]
 license = "MIT/Apache-2.0"
 readme = "README.md"