analyzer: add note about -fdump-ipa-analyzer to internal docs

gcc/ChangeLog:
	* doc/analyzer.texi (Overview): Add note about
	-fdump-ipa-analyzer.

gcc/ChangeLog

+2020-01-15  David Malcolm  <dmalcolm@redhat.com>
+
+	* doc/analyzer.texi (Overview): Add note about
+	-fdump-ipa-analyzer.
+
 2020-01-15  Wilco Dijkstra  <wdijkstr@arm.com>
 
 	PR tree-optimization/93231

gcc/doc/analyzer.texi

@@ -28,6 +28,8 @@ do whole-program analysis).
 The implementation is read-only: it doesn't attempt to change anything,
 just emit warnings.
 
+The gimple representation can be seen using @option{-fdump-ipa-analyzer}.
+
 First, we build a @code{supergraph} which combines the callgraph and all
 of the CFGs into a single directed graph, with both interprocedural and
 intraprocedural edges.  The nodes and edges in the supergraph are called