doc: Add a missing '*' to the documentation of CoglFilterReturn
doc: Add a missing '*' to the documentation of CoglFilterReturn

djdeath/cogl-android,gcampax/cogl,gcampax/cogl,djdeath/cogl,gcampax/cogl,djdeath/cogl-android,djdeath/cogl,gcampax/cogl,djdeath/cogl,djdeath/cogl-android