gn2bp: fix arg sanitization

I guess this is essentially a noop.

Test: none
Change-Id: I9524827ad8326737a6c3bd4330433da7b7c12611
diff --git a/tools/gn2bp/gen_android_bp b/tools/gn2bp/gen_android_bp
index 9e7fc5d..070bb9a 100755
--- a/tools/gn2bp/gen_android_bp
+++ b/tools/gn2bp/gen_android_bp
@@ -633,7 +633,7 @@
     # Just to be on the safe side, create a deep-copy.
     self.target = copy.deepcopy(target)
     # Convert ['--param=value'] to ['--param', 'value'] for consistency.
-    self.target.args = [str for it in target.args for str in it.split('=')]
+    self.target.args = [str for it in self.target.args for str in it.split('=')]
 
   def _has_arg(self, arg):
     return arg in self.target.args