[submodule]: update sonic-platform-daemons

* 664f0e2 2021-07-14 | [xrcvd]: Removed undefined symbol 'sfp_status_helper' (sonic-net#204) (HEAD, origin/202012) [Prince George]
* 1b2d016 2021-06-16 | [CI] sonic-config-engine now depends on SONiC YANG packages (sonic-net#194) [Joe LeVeque]
* 1cf5996 2021-07-14 | Introduce mgmtinit delay after transceiver module insertion (sonic-net#201) [Prince George]

Signed-off-by: Guohan Lu <lguohan@gmail.com>