Convert use's to anchored_use_paths

This commit specifies a few modules in use statements with the `self::` prefix.
This commit is motivated by the fact that the current Rust 2018 default is
`anchored_use_paths`, not `uniform_paths`.

build.rs

@@ -36,7 +36,7 @@ mod parse_error {
     }
 }
 
-use triple::{Endianness, PointerWidth, Triple};
+use self::triple::{Endianness, PointerWidth, Triple};
 
 /// Assuming `target` is a path to a custom target json config file, open it
 /// and build a `Triple` using its contents.

src/lib.rs

@@ -32,7 +32,7 @@ mod targets;
 #[macro_use]
 mod triple;
 
-pub use host::HOST;
-pub use parse_error::ParseError;
-pub use targets::{Architecture, BinaryFormat, Environment, OperatingSystem, Vendor};
-pub use triple::{CallingConvention, Endianness, PointerWidth, Triple};
+pub use self::host::HOST;
+pub use self::parse_error::ParseError;
+pub use self::targets::{Architecture, BinaryFormat, Environment, OperatingSystem, Vendor};
+pub use self::triple::{CallingConvention, Endianness, PointerWidth, Triple};