points-to: filter out incompatible function pointers
points-to: filter out incompatible function pointers

if we have function pointer that points to a function
with different prototypes, we may be pretty sure it is due to
overapproximation, because such a binding cannot happen during runtime

Signed-off-by: Marek Chalupa <a05df156a69ad59faa9af9b666ef78009594c145@gmail.com>

mchalupa/dg,mchalupa/dg,mchalupa/dg,mchalupa/dg