[roll third_party/pigweed] pw_{rpc, transfer}: Remove unused imports

Original-Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/95365

https://pigweed.googlesource.com/pigweed/pigweed
third_party/pigweed Rolled-Commits: d20c1242ea54ac7..6c0716d7fb60f18
Roller-URL: https://ci.chromium.org/b/8813691802624917761
Cq-Cl-Tag: roller-builder:pigweed-experimental-roller
Cq-Cl-Tag: roller-bid:8813691802624917761
CQ-Do-Not-Cancel-Tryjobs: true
Change-Id: I08cf5428bd981058518ee06c479516826ec4a3fc
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/experimental/+/95408
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>
1 file changed