This update adds the setup_patch_repo.sh script to starlingx/update
for use by the patch-iso utility. This file was missed from initial
seeding of StarlingX.
Change-Id: I48b7caa2a41347ada6185e8d262d3b3d330dd37e
Partial-Bug: 1863011
Signed-off-by: Don Penney <don.penney@windriver.com>