[clang] nonblocking/nonallocating attributes: 2nd pass caller/callee analysis (PR #99656)

[Doug Wyatt via cfe-commits]

================
@@ -4712,12 +4715,13 @@ class FunctionEffect {
 public:
   /// Identifies the particular effect.
   enum class Kind : uint8_t {
-    None = 0,
-    NonBlocking = 1,
-    NonAllocating = 2,
-    Blocking = 3,
-    Allocating = 4
+    NonBlocking = 0,
+    NonAllocating = 1,
+    Blocking = 2,
+    Allocating = 3,
+
----------------
dougsonos wrote:

`Last` seems to be the most common name for that last value...

```
enum class ComparisonCategoryType : unsigned char {
  PartialOrdering,
  WeakOrdering,
  StrongOrdering,
  First = PartialOrdering,
  Last = StrongOrdering
};

enum class Lang { C = 0, CXX, LastValue = CXX };

enum class SyncScope {
  SystemScope,
  DeviceScope,
  WorkgroupScope,
  WavefrontScope,
  SingleScope,
  HIPSingleThread,
  HIPWavefront,
  HIPWorkgroup,
  HIPAgent,
  HIPSystem,
  OpenCLWorkGroup,
  OpenCLDevice,
  OpenCLAllSVMDevices,
  OpenCLSubGroup,
  Last = OpenCLSubGroup
```

https://github.com/llvm/llvm-project/pull/99656