floss: Remove rootcanal build rules

build.py contains rules for building and testing the LMP
code, that were added when it was discussed to build
the LMP for the emulator.

Now that the emulator by default builds the rust LMP
using the Cargo.toml files, these rules are no longer
necessary.

Furthermore, they pull crate dependencies from the chrome
directory, which is likely to cause issues in the future
as all other build rules for LMP use the crate versionned
from AOSP.

Test: NA
Bug: 238726856
Change-Id: I786f35939b707d5eecff4281be4fb7aee19e4e7b

build.py

@@ -70,7 +70,6 @@ VALID_TARGETS = [
     'hosttools',  # Build the host tools (i.e. packetgen)
     'main',  # Build the main C++ codebase
     'prepare',  # Prepare the output directory (gn gen + rust setup)
-    'rootcanal',  # Build Rust targets for RootCanal
     'rust',  # Build only the rust components + copy artifacts to output dir
     'test',  # Run the unit tests
     'utils',  # Build Floss utils
@@ -459,15 +458,6 @@ class HostBuild():
         """
         self._rust_build()
 
-    def _target_rootcanal(self):
-        """ Build rust artifacts for RootCanal in an already prepared environment.
-        """
-        cmd = ['cargo', 'build']
-        if not self.args.rust_debug:
-            cmd.append('--release')
-
-        self.run_command('rust', cmd, cwd=os.path.join(self.platform_dir, 'bt/tools/rootcanal'), env=self.env)
-
     def _target_main(self):
         """ Build the main GN artifacts in an already prepared environment.
         """
@@ -485,7 +475,6 @@ class HostBuild():
             rust_test_cmd = rust_test_cmd + [self.args.test_name, "--", "--test-threads=1", "--nocapture"]
 
         self.run_command('test', rust_test_cmd, cwd=os.path.join(self.platform_dir, 'bt'), env=self.env)
-        self.run_command('test', rust_test_cmd, cwd=os.path.join(self.platform_dir, 'bt/tools/rootcanal'), env=self.env)
 
         # Host tests second based on host test list
         for t in HOST_TESTS:
@@ -566,7 +555,6 @@ class HostBuild():
         # Remove Cargo.lock that may have become generated
         cargo_lock_files = [
             os.path.join(self.platform_dir, 'bt', 'Cargo.lock'),
-            os.path.join(self.platform_dir, 'bt', 'tools', 'rootcanal', 'Cargo.lock'),
         ]
         for lock_file in cargo_lock_files:
             try:
@@ -597,8 +585,6 @@ class HostBuild():
             self._target_prepare()
         elif self.target == 'hosttools':
             self._target_hosttools()
-        elif self.target == 'rootcanal':
-            self._target_rootcanal()
         elif self.target == 'rust':
             self._target_rust()
         elif self.target == 'docs':