pw_env_setup: Fix variable name typo
pw_env_setup: Fix variable name typo

Change-Id: I6f51514fef6b4a7cf0447f678e2cdcb9c49d03cb
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/108228
Pigweed-Auto-Submit: Alexei Frolov <a1b001416a8cf9aaea32a3411f8f3c0793ebc0b5@google.com>
Commit-Queue: Auto-Submit <14637eda5603879df170705285bf30f5996692f0@pigweed.google.com.iam.gserviceaccount.com>
Reviewed-by: Rob Mohr <d07614a8a0b466db08f68224f87d738b0f9615cf@google.com>

google/pigweed,google/pigweed,google/pigweed,google/pigweed,google/pigweed,google/pigweed,google/pigweed,google/pigweed,google/pigweed,google/pigweed