Streamline dump control options

- Rename `--dump-treei` option to `--dumpi-tree`, which itself is now a
  special case of `--dumpi-<tag>` where tag can be a magic word, or a
  filename
- Control dumping via static `dump*()` functions, analogous to `debug()`
- Make dumping independent of the value of `debug()` (so dumping always
  works even without the debug flag)
- Add separate `--dumpi-graph` for dumping V3Graphs, which is again a
  special case of `--dumpi-<tag>`
- Alias `--dump-<tag>` to `--dumpi-<tag> 3` as before

src/V3EmitCMake.cpp

@@ -26,13 +26,14 @@
 
 #include <memory>
 
-//######################################################################
-// Emit statements
+VL_DEFINE_DEBUG_FUNCTIONS;
+
+// ######################################################################
+//  Emit statements
 
 class CMakeEmitter final {
 
     // METHODS
-    VL_DEBUG_FUNC;  // Declare debug()
 
     // STATIC FUNCTIONS