framework: Remove signal type __FWK_ID_TYPE_SIGNAL
Created by: girishpathak
This change removes unused types __FWK_ID_TYPE_SIGNAL and 'struct signal' which are not needed as it's use was removed in the below commit(part of light event patchset)
f74c34fc framework, dvfs: Remove signals.
Change-Id: I46b0c90ffc55893df5c2cebf461637ba91a8f3ce Signed-off-by: Girish Pathak girish.pathak@arm.com