alphablending: Improve critical regions

Change-Id: Ia1551fded4a84302a1afd491be0dcedeea788895
alphablending: Remove audio mixing

Change-Id: I0127698677e789c671500ef058884c23672843ab
alphablending: Fix warning while unreferencing NULL caps

Change-Id: I8587722afa93480c8867e234613079c632e0eedd
kmsalphablendingportdata: Add mini object

Change-Id: I8ccf83fc5126e1e4afc743552b5d74904e2cd83f
kmsalphablending: Use mini-object for port data

Change-Id: I5a44d16a66e5f6fc25d8aaafe768bcb76320fb06
alphablending: Do not propagate EOS once it is processed.

Change-Id: Ifba690c062849e175ae6e03328deec14180aad14
alphablending: Destroy port data correctly when port is unhandled

Change-Id: I2b226d826e666dc2ae1d6b51c9157a6419212538
alphablending: Remove extra 'd' while printing debug info

Change-Id: I7e10dccdd2e59a7406469c5604394d9a65c8f6cb
kmsalphablending: Synchronize elements which receive data from any source after linking them

Change-Id: Id6dc50840b43288375aaa1f2e5d264209f73c73b
kmsalphablending: Fix race condition accesing to elements in port data when they are deleted

Change-Id: I1caed134751afa55a0496273af2099e08ba79e05