coap: update libcoap to fix its broken submodule pointer

Though IDF v4.0 does not have dependency on `tinydtls` repository
within libcoap, it created problem in recursive clone. This commit
picks up change from upstream libcoap release-v4.2.0 to update
`tinydtls` repository pointer.

More information at:
https://github.com/obgm/libcoap/pull/531

Merges https://github.com/espressif/esp-idf/pull/5626
This commit is contained in:
Mahavir Jain
2020-09-14 10:59:52 +05:30
parent 6093407d78
commit 374b756f6b