add dquotes

Author: atlazar

example-egl/bash_script/build_toolchain.sh

@@ -49,7 +49,7 @@ set -x
 		--api=$ANDROID_API --install-dir=$TOOLCHAIN_DIR \
 		--arch=$ARCH --stl libc++
 # The command above includes the wrong headers due to a bug in the android sdk and/or cmake. The following two commands fix this issue.
-rm -rf $TOOLCHAIN_DIR/sysroot/usr
+rm -rf "$TOOLCHAIN_DIR/sysroot/usr"
 cp -r  "$ANDROID_HOME/ndk-bundle/platforms/android-$ANDROID_API/arch-$ARCH/usr" "$TOOLCHAIN_DIR/sysroot/usr"
 set +x
 printf "Standalone toolchain ready\n"