effects: make :terminates_globally functional on recursive functions

As with loop, it's hard to prove termination of recursive call automatically.
But with this commit we can manually specify termination at least.
```julia
Base.@assume_effects :terminates_globally function recur_termination1(x)
    x == 1 && return 1
    1 < x < 20 || throw("bad")
    return x * recur_termination1(x-1)
end
@test fully_eliminated() do
    recur_termination1(12)
end

Base.@assume_effects :terminates_globally function recur_termination2(x)
    x == 1 && return 1
    1 < x < 20 || throw("bad")
    return _recur_termination2(x)
end
_recur_termination2(x) = x * recur_termination2(x-1)
@test fully_eliminated() do
    recur_termination2(12)
end
```

base/compiler/abstractinterpretation.jl

@@ -596,9 +596,13 @@ function abstract_call_method(interp::AbstractInterpreter, method::Method, @nosp
     end
     if edgecycle
         # Some sort of recursion was detected. Even if we did not limit types,
-        # we cannot guarantee that the call will terminate.
-        edge_effects = tristate_merge(edge_effects,
-            Effects(EFFECTS_TOTAL, terminates=TRISTATE_UNKNOWN))
+        # we cannot guarantee that the call will terminate, unless specified explicitly
+        if decode_effects_override(method.purity).terminates_globally
+            terminates_override = ALWAYS_TRUE
+        else
+            terminates_override = TRISTATE_UNKNOWN
+        end
+        edge_effects = Effects(edge_effects, terminates = terminates_override)
     end
     return MethodCallResult(rt, edgecycle, edgelimited, edge, edge_effects)
 end

test/compiler/inline.jl

@@ -1069,3 +1069,21 @@ end
 @test fully_eliminated() do
     issue41694(2)
 end
+
+Base.@assume_effects :terminates_globally function recur_termination1(x)
+    x == 1 && return 1
+    1 < x < 20 || throw("bad")
+    return x * recur_termination1(x-1)
+end
+@test fully_eliminated() do
+    recur_termination1(12)
+end
+Base.@assume_effects :terminates_globally function recur_termination2(x)
+    x == 1 && return 1
+    1 < x < 20 || throw("bad")
+    return _recur_termination2(x)
+end
+_recur_termination2(x) = x * recur_termination2(x-1)
+@test fully_eliminated() do
+    recur_termination2(12)
+end