usb-dbg: add meson option for enabling ME support

Add a meson option called me_support for enabling ME related feature.
Default value is true (enable)

Tested on Bletchley with me_support false

Signed-off-by: Potin Lai <potin.lai@quantatw.com>
Change-Id: I7e9f632b53c68b95f1d63f5408a9025f2a20fc3a
diff --git a/meson.build b/meson.build
index 9679cc5..4736ea0 100644
--- a/meson.build
+++ b/meson.build
@@ -47,6 +47,14 @@
     language : 'cpp')
 endif
 
+if get_option('me_support')
+  add_project_arguments(
+    cpp.get_supported_arguments([
+        '-DME_SUPPORT',
+    ]),
+    language : 'cpp')
+endif
+
 root_inc = include_directories('.', 'include')
 
 # Dependencies