use actual names (rust-lang#1594)

Author: tshepang

src/doc/rustc-dev-guide/src/SUMMARY.md

@@ -75,7 +75,7 @@
 
 - [Prologue](./part-3-intro.md)
 - [Command-line arguments](./cli.md)
-- [The Rustc Driver and Interface](./rustc-driver.md)
+- [rustc_driver and rustc_interface](./rustc-driver.md)
     - [Example: Type checking](./rustc-driver-interacting-with-the-ast.md)
     - [Example: Getting diagnostics](./rustc-driver-getting-diagnostics.md)
 - [Syntax and the AST](./syntax-intro.md)

src/doc/rustc-dev-guide/src/rustc-driver.md

@@ -1,4 +1,4 @@
-# The Rustc Driver and Interface
+# `rustc_driver` and `rustc_interface`
 
 The [`rustc_driver`] is essentially `rustc`'s `main()` function. It acts as
 the glue for running the various phases of the compiler in the correct order,