Move examples to a subdirectory

examples/rp/.cargo/config.toml

@@ -0,0 +1,19 @@
+[unstable]
+build-std = ["core"]
+
+[target.'cfg(all(target_arch = "arm", target_os = "none"))']
+runner = "probe-run-rp --chip RP2040"
+
+rustflags = [
+  # LLD (shipped with the Rust toolchain) is used as the default linker
+  "-C", "link-arg=--nmagic",
+  "-C", "link-arg=-Tlink.x",
+  "-C", "link-arg=-Tlink-rp.x",
+  "-C", "link-arg=-Tdefmt.x",
+
+  # Code-size optimizations.
+  "-Z", "trap-unreachable=no",
+]
+
+[build]
+target = "thumbv6m-none-eabi"        # Cortex-M0 and Cortex-M0+