C++: Use isFromMacroDefinition for exclusion

The `SignedOverflowCheck.ql` query was very slow on certain snapshots
(jluttine/suitesparse and Chromium) due to bad magic in
`MacroInvocation::getAnAffectedElement_dispred#fb`. This commit doesn't
fix the bad magic but changes the exclusion mechanism to use a predicate
where we can better control the magic and optimization.

The query should also give more good results due to this new exclusion
mechanism, which is the same one used in its sibling,
`PointerOverflow.ql`.

Author: jbj

cpp/ql/src/Likely Bugs/Arithmetic/SignedOverflowCheck.ql

@@ -14,6 +14,7 @@
 import cpp
 private import semmle.code.cpp.valuenumbering.GlobalValueNumbering
 private import semmle.code.cpp.rangeanalysis.SimpleRangeAnalysis
+private import semmle.code.cpp.commons.Exclusions
 
 from RelationalOperation ro, AddExpr add, Expr expr1, Expr expr2
 where
@@ -22,7 +23,7 @@ where
   ro.getAnOperand() = expr2 and
   globalValueNumber(expr1) = globalValueNumber(expr2) and
   add.getUnspecifiedType().(IntegralType).isSigned() and
-  not exists(MacroInvocation mi | mi.getAnAffectedElement() = add) and
+  not isFromMacroDefinition(add) and
   exprMightOverflowPositively(add) and
   exists(Compilation c | c.getAFileCompiled() = ro.getFile() |
     not c.getAnArgument() = "-fwrapv" and