Fix bazel build of p4 runtime protos

Change-Id: I72f8dc332fe1cfff879a7378d0953cd872ee37ac
diff --git a/tools/build/bazel/p4lang_workspace.bzl b/tools/build/bazel/p4lang_workspace.bzl
index 860f621..d1bd40e 100644
--- a/tools/build/bazel/p4lang_workspace.bzl
+++ b/tools/build/bazel/p4lang_workspace.bzl
@@ -1,7 +1,7 @@
 GITHUB_BASE_URL = "https://github.com"
 
-PI_COMMIT_SHORT = "219b3d6"
-PI_COMMIT = "219b3d67299ec09b49f433d7341049256ab5f512"
+PI_COMMIT_SHORT = "59c9409"
+PI_COMMIT = "59c940916b4f5b182f33b4788d8c410972eaecce"
 PI_REPO = "p4lang/PI"
 
 GOOGLE_RPC_COMMIT_SHORT = "916e66d"