development/hhvm: Fix rust-nightly file names.

Looks like some copy and paste mistake was made here. This
was previously failing because no such file was downloaded.

I've adjusted the names of the file now.

Signed-off-by: Andrew Clemons <andrew.clemons@gmail.com>

Signed-off-by: Willy Sudiarto Raharjo <willysr@slackbuilds.org>

development/hhvm/hhvm.SlackBuild

@@ -94,9 +94,9 @@ tar zxvf $CWD/brotli-v1.0.9.tar.gz \
   --strip-components=1
 
 mkdir -p third-party/rustc/bundled_rust-prefix/src/bundled_rust
-install -m 0644 -D $CWD/rustc-2021-11-29-rust-nightly-x86_64-unknown-linux-gnu.tar.gz \
-  third-party/rustc/bundled_rust-prefix/src/rustc-2021-11-29-rust-nightly-x86_64-unknown-linux-gnu.tar.gz
-tar zxvf $CWD/rustc-2021-11-29-rust-nightly-x86_64-unknown-linux-gnu.tar.gz \
+install -m 0644 -D $CWD/rust-nightly-x86_64-unknown-linux-gnu.tar.gz \
+  third-party/rustc/bundled_rust-prefix/src/rust-nightly-x86_64-unknown-linux-gnu.tar.gz
+tar zxvf $CWD/rust-nightly-x86_64-unknown-linux-gnu.tar.gz \
   -C third-party/rustc/bundled_rust-prefix/src/bundled_rust \
   --strip-components=1