[NaCl SDK] A bunch of spelling fixes.

native_client_sdk/src/build_tools/make_simple.py

 # Copyright (c) 2012 Google Inc. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 """This is a simplified Makefile generator for single-target gyp files.
 It was originally designed for generating readable Makefiles for the
 the NaCL examples.
 """
 
 # pylint: disable=C0301
@@ skipping 276 matching lines @@
     'all_configs': ' '.join(target_info['configurations'].keys()),
   }
 
   params.update(settings_map)
   makefile.write(preamble % params)
 
   for target_info in target_dicts.values():
     WriteTarget(makefile, target_info)
 
   makefile.write('''
-# include (if they exists) the .d dependancy files that the compiler generates
+# include (if they exists) the .d dependency files that the compiler generates
 -include $(DEPFILES)
 
 endif
 ''')
 
   makefile.close()