build-python: Add --with-pic to fix the native static libffi on x86_64

This fixes building python on x86_64 linux after
fabc4571b2.

build-python.sh

@@ -92,7 +92,7 @@ if [ -z "$HOST" ]; then
     [ -z "$CLEAN" ] || rm -rf $BUILDDIR
     mkdir -p $BUILDDIR
     cd $BUILDDIR
-    ../configure --prefix="$PREFIX" --disable-symvers --disable-docs --disable-shared
+    ../configure --prefix="$PREFIX" --disable-symvers --disable-docs --disable-shared --with-pic
     $MAKE -j$CORES
     $MAKE install
     cd ../..