Merge pull request 'add command to download prerequisites' (#1) from Pavel/sh-elf-gcc:master into master

Reviewed-on: https://gitea.planet-casio.com/Lephenixnoir/sh-elf-gcc/pulls/1

configure.sh

@@ -55,6 +55,12 @@ fi
 echo "$TAG Extracting $ARCHIVE..."
 unxz -c < $ARCHIVE | tar -xf -
 
+# Download prerequisites
+
+cd gcc-$VERSION
+./contrib/download_prerequisites
+cd ..
+
 # Create build folder
 
 [[ -d "build" ]] && rm -rf build