roll: pigweed, pw_toolchain: pw_spi_linux: Remove linkage specification from cli main

According to the C++ standard, the main function shall not be declared
with a linkage-specification. An upcoming Crosstool release includes
[20-1706 [Clang] Strengthen checks for `main`  to meet
`[basic.start.main]p3`’s requirements (#101853)](http://go/compilers/37ec6e5f12afe4a37872bf28f280423696f39019),
which will lead to breakages when compiling `extern "C" int main...`.

This CL removes the linkage specification from pw_spi_linux_cli's main
function and moves the main function to the global namespace.

Original-Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/230291

https://pigweed.googlesource.com/pigweed/pigweed
pigweed, pw_toolchain Rolled-Commits: 7654e112c63755f..704a5f3dde6a006
Roller-URL: https://ci.chromium.org/b/8739405184993178545
GitWatcher: ignore
CQ-Do-Not-Cancel-Tryjobs: true
Change-Id: Id2bce13173e75bdce6ef915323356550410c08e1
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/quickstart/bazel/+/230451
Bot-Commit: Pigweed Roller <pigweed-roller@pigweed-service-accounts.iam.gserviceaccount.com>
Commit-Queue: Pigweed Roller <pigweed-roller@pigweed-service-accounts.iam.gserviceaccount.com>
Lint: Lint 🤖 <android-build-ayeaye@system.gserviceaccount.com>
diff --git a/MODULE.bazel b/MODULE.bazel
index 2117366..3c662ac 100644
--- a/MODULE.bazel
+++ b/MODULE.bazel
@@ -48,8 +48,8 @@
     module_name = "pigweed",
     # ROLL: Warning: this entry is automatically updated.
     # ROLL: Last updated 2024-08-16.
-    # ROLL: By https://cr-buildbucket.appspot.com/build/8739416221375173457.
-    commit = "7654e112c63755f93c7b59e2fb7ab31a84bcb8fe",
+    # ROLL: By https://cr-buildbucket.appspot.com/build/8739405184993178545.
+    commit = "704a5f3dde6a006418cbf01a3b9a67e6957f1164",
     remote = "https://pigweed.googlesource.com/pigweed/pigweed",
 )
 
@@ -57,8 +57,8 @@
     module_name = "pw_toolchain",
     # ROLL: Warning: this entry is automatically updated.
     # ROLL: Last updated 2024-08-16.
-    # ROLL: By https://cr-buildbucket.appspot.com/build/8739416221375173457.
-    commit = "7654e112c63755f93c7b59e2fb7ab31a84bcb8fe",
+    # ROLL: By https://cr-buildbucket.appspot.com/build/8739405184993178545.
+    commit = "704a5f3dde6a006418cbf01a3b9a67e6957f1164",
     remote = "https://pigweed.googlesource.com/pigweed/pigweed",
     strip_prefix = "pw_toolchain_bazel",
 )