Add wg-llvm stream to table.

Author: davidtwco

README.md

@@ -48,7 +48,7 @@ active working groups are listed below:
 Name                                                      | Status       | Short Description                                                                                  | Zulip Stream
 ----                                                      | ------       | -----------------                                                                                  | ------------
 [Async-await Implementation](working-groups/async-await/) | Active       | Implementing async-await                                                                           | [#t-compiler/wg-async-await][async-await_stream]
-[LLVM](working-groups/llvm/)                              | Incubating   | Working with LLVM upstream to represent Rust in its development                                    | N/A
+[LLVM](working-groups/llvm/)                              | Incubating   | Working with LLVM upstream to represent Rust in its development                                    | [#t-compiler/wg-llvm][llvm_stream]
 [Non-Lexical Lifetimes (NLL)](working-groups/nll/)        | Winding down | Implementing non-lexical lifetimes                                                                 | [#t-compiler/wg-nll][nll_stream]
 [Traits](working-groups/traits/)                          | Active       | Improving the trait-system design + implementation                                                 | [#t-compiler/wg-traits][traits_stream]
 [Parallel-rustc](working-groups/parallel-rustc/)          | Active       | Making parallel compilation the default for rustc                                                  | [#t-compiler/wg-parallel-rustc][parallel-rustc_stream]
@@ -74,6 +74,7 @@ Name                                                      | Status       | Short
 
 [Weekly, in Zulip]: #meeting-calendar
 [nll_stream]: https://rust-lang.zulipchat.com/#narrow/stream/122657-t-compiler.2Fwg-nll
+[llvm_stream]: https://rust-lang.zulipchat.com/#narrow/stream/187780-t-compiler.2Fwg-llvm
 [meta_stream]: https://rust-lang.zulipchat.com/#narrow/stream/185694-t-compiler.2Fwg-meta
 [rls20_stream]: https://rust-lang.zulipchat.com/#narrow/stream/185405-t-compiler.2Fwg-rls-2.2E0
 [traits_stream]: https://rust-lang.zulipchat.com/#narrow/stream/144729-t-compiler.2Fwg-traits