kmsalphableding: Improve port configuration

Change-Id: Ib8d644945b4452beb04e67c364aca60f35cb700a
kmsalphablending: Replace KmsGenericStructure for KmsRefStruct

KmsRefStruct is a lighther structure wich is expected to be enough
for cases where you just need to provide data among callbacks keeping
references among them and release the data when the last ref reaches
the value of zero.

Change-Id: I5bd555bc7de1637efeebaaa2ce3a768ff2bf7235
kmsalphablending: Cosmetic changes

Change-Id: I96502c09651f16af6e0609ebfd653fa94b022916
kmsalphablending: Do not allocate memory to be used as keys in a hashmap

Change-Id: Ie4f0554fd3da290acdbae26e57c58394390316b4