targets/rp2: Set PICO_DEFAULT_LINKER_SCRIPT to upstream linker script

Change-Id: I48583bf81f05de813721e535e8c3804c5a1ad346
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/quickstart/bazel/+/242372
Commit-Queue: Auto-Submit <auto-submit@pigweed-service-accounts.iam.gserviceaccount.com>
Presubmit-Verified: CQ Bot Account <pigweed-scoped@luci-project-accounts.iam.gserviceaccount.com>
Commit-Queue: Dave Roth <davidroth@google.com>
Lint: Lint 🤖 <android-build-ayeaye@system.gserviceaccount.com>
Pigweed-Auto-Submit: Dave Roth <davidroth@google.com>
Reviewed-by: Wyatt Hepler <hepler@google.com>
diff --git a/targets/rp2/BUILD.bazel b/targets/rp2/BUILD.bazel
index 73ed7e5..bacbd17 100644
--- a/targets/rp2/BUILD.bazel
+++ b/targets/rp2/BUILD.bazel
@@ -51,6 +51,9 @@
         "@platforms//cpu:armv6-m",
         "@pw_toolchain//constraints/arm_mcpu:cortex-m0",
     ],
+    flags = flags_from_dict({
+        "@pico-sdk//bazel/config:PICO_DEFAULT_LINKER_SCRIPT": "@pigweed//targets/rp2040:rp2040_linker_script",
+    }),
     parents = [":rp2_common"],
 )
 
@@ -63,6 +66,9 @@
         "@platforms//cpu:armv8-m",
         "@pw_toolchain//constraints/arm_mcpu:cortex-m33",
     ],
+    flags = flags_from_dict({
+        "@pico-sdk//bazel/config:PICO_DEFAULT_LINKER_SCRIPT": "@pigweed//targets/rp2040:rp2350_linker_script",
+    }),
     parents = [":rp2_common"],
 )