Use relative path in symlink

Specifying the absolute path as the target to the symlink causes
portability problems because when we eventually archive up the result
for distribution, the absolute paths will be incorrect on the target
systems.

mcrouter/scripts/get_and_build_by_make.sh

@@ -28,7 +28,7 @@ mkdir -p "$INSTALL_DIR/lib"
 # As a workaround, we just upfront link lib64 -> lib so all dependency artifacts
 # end up in $INSTALL_DIR/lib which that build script *can* find.
 if [ ! -e "$INSTALL_DIR/lib64" ]; then
-    ln -sf "$INSTALL_DIR/lib" "$INSTALL_DIR/lib64"
+    ln -sf lib "$INSTALL_DIR/lib64"
 fi
 
 cd "$(dirname "$0")" || ( echo "cd fail"; exit 1 )