[202012][sonic-platform-common] submodule update (#9297)

6f198d0 (HEAD -> 202012, origin/202012) [Y-Cable][Broadcom] upgrade to support Broadcom Y-Cable API to release (#230)
1c3e422 SSD Health: Retrieve SSD health and temperature values from generic SSD info (#229)

Signed-off-by: vaibhav-dahiya <[email protected]>