rustup: Don't do verbose tarball extraction

This creates an enormous amount of spew.

Author: brson

src/etc/rustup.sh

@@ -440,7 +440,7 @@ install_package() {
     install_script="$2"
 
     msg "Extracting ${tarball_name}"
-    (cd "${CFG_TMP_DIR}" && "${CFG_TAR}" -xvf "${tarball_name}")
+    (cd "${CFG_TMP_DIR}" && "${CFG_TAR}" -xzf "${tarball_name}")
     if [ $? -ne 0 ]; then
         rm -Rf "${CFG_TMP_DIR}"
         err "failed to unpack installer"