toolchain: Use multiple processes to build glslang
diff --git a/update_external_sources.sh b/update_external_sources.sh
index ea294f6..780d849 100755
--- a/update_external_sources.sh
+++ b/update_external_sources.sh
@@ -64,7 +64,7 @@
    mkdir -p build
    cd build
    cmake -D CMAKE_BUILD_TYPE=Release ..
-   make
+   make -j $(nproc)
    make install
 }