Add option to avoid thneed (#21577)

* add option to avoid thneed

* cleaner

Co-authored-by: Willem Melching <willem.melching@gmail.com>

* fix USE_THNEED in modeld

* cleanup

Co-authored-by: Willem Melching <willem.melching@gmail.com>
Co-authored-by: Comma Device <device@comma.ai>

SConstruct

@@ -51,6 +51,11 @@ AddOption('--external-sconscript',
           dest='external_sconscript',
           help='add an external SConscript to the build')
 
+AddOption('--no-thneed',
+          action='store_true',
+          dest='no_thneed',
+          help='avoid using thneed')
+
 real_arch = arch = subprocess.check_output(["uname", "-m"], encoding='utf8').rstrip()
 if platform.system() == "Darwin":
   arch = "Darwin"