west: Remove sysbuild being enabled by default

Signed-off-by: Marek Maškarinec <marek.maskarinec@hardwario.com>

scripts/west_commands/build.py

@@ -595,12 +595,7 @@ def _run_cmake(self, board, origin, cmake_opts):
         if user_args:
             cmake_opts.extend(shlex.split(user_args))
 
-        config_sysbuild = config_getboolean('sysbuild', None)
-
-        if config_sysbuild is None:
-            # If no option is set, then enable sysbuild globally
-            config_sysbuild = True
-
+        config_sysbuild = config_getboolean('sysbuild', False)
         if self.args.sysbuild or (config_sysbuild and not self.args.no_sysbuild):
             cmake_opts.extend(['-S{}'.format(SYSBUILD_PROJ_DIR),
                                '-DAPP_DIR:PATH={}'.format(self.source_dir)])