[roll third_party/pigweed] pw_rpc: Make service/method ID private in the Java APIs

Service and method IDs are internal to pw_rpc and should not be used
externally.

Original-Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/97681

https://pigweed.googlesource.com/pigweed/pigweed
third_party/pigweed Rolled-Commits: 2c81a8331d07a84..88ee2e643d5e3dc
Roller-URL: https://ci.chromium.org/b/8811706595784224033
Cq-Cl-Tag: roller-builder:pigweed-experimental-roller
Cq-Cl-Tag: roller-bid:8811706595784224033
CQ-Do-Not-Cancel-Tryjobs: true
Change-Id: I405867713f80107025a1ba9dd378423ed17fc5e9
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/experimental/+/97795
Bot-Commit: Pigweed Integration Roller <pigweed-integration-roller@pigweed.google.com.iam.gserviceaccount.com>
Commit-Queue: Pigweed Integration Roller <pigweed-integration-roller@pigweed.google.com.iam.gserviceaccount.com>
diff --git a/third_party/pigweed b/third_party/pigweed
index 2c81a83..88ee2e6 160000
--- a/third_party/pigweed
+++ b/third_party/pigweed
@@ -1 +1 @@
-Subproject commit 2c81a8331d07a842eb859a409edf0bcc605a3cf7
+Subproject commit 88ee2e643d5e3dc16780e8ee8b1893188d94b88e