build: build with v8 gdbjit support on supported platform

Build it with gdbjit support on supported platforms by default
allows debugging JIT-compiled code in gdb when it's also enabled
at run time (via --gdbjit). Simply building it in should not
incur an overhead if it's not also enabled at run time.

Author: joyeecheung

configure.py

@@ -1822,7 +1822,16 @@ def configure_v8(o, configs):
   o['variables']['v8_enable_webassembly'] = 0 if options.v8_lite_mode else 1
   o['variables']['v8_enable_javascript_promise_hooks'] = 1
   o['variables']['v8_enable_lite_mode'] = 1 if options.v8_lite_mode else 0
-  o['variables']['v8_enable_gdbjit'] = 1 if options.gdb else 0
+  is_gdbjit_supported_arch = (
+      'x64' in o['variables']['target_arch'] or
+      'ia32' in o['variables']['target_arch'] or
+      'ppc64' in o['variables']['target_arch']
+  )
+  is_linux = flavor == 'linux'
+  if (options.gdb is not None):
+    o['variables']['v8_enable_gdbjit'] = 1 if options.gdb else 0
+  else:
+    o['variables']['v8_enable_gdbjit'] = 1 if is_gdbjit_supported_arch and is_linux else 0
   o['variables']['v8_optimized_debug'] = 0 if options.v8_non_optimized_debug else 1
   o['variables']['dcheck_always_on'] = 1 if options.v8_with_dchecks else 0
   o['variables']['v8_enable_object_print'] = 0 if options.v8_disable_object_print else 1