Flipping `-iree-experimental-streams` flag to default true. (#7659)

iree/compiler/Translation/IREEVM.cpp

diff --git a/iree/compiler/Translation/IREEVM.cpp b/iree/compiler/Translation/IREEVM.cpp
index b031247..e8ef7ec 100644
--- a/iree/compiler/Translation/IREEVM.cpp
+++ b/iree/compiler/Translation/IREEVM.cpp
@@ -35,7 +35,7 @@
   static llvm::cl::opt<bool> *enableFlag = new llvm::cl::opt<bool>{
       "iree-experimental-streams",
       llvm::cl::desc("Enables experimental stream dialect pipelines."),
-      llvm::cl::init(false),
+      llvm::cl::init(true),
   };
   return *enableFlag;
 }