Revert "s/PRODUCT-SERVICES/PRODUCT_SERVICES/g"

This reverts commit 77c778c040bf8717d6c5d4066b533b3d5ece8050.

Reason for revert: git-master break on 4960355

Change-Id: I2fd272c63ef496067f12852bcf98ffc1194c54bf
diff --git a/tools/releasetools/add_img_to_target_files.py b/tools/releasetools/add_img_to_target_files.py
index 66fe18b..932fab9 100755
--- a/tools/releasetools/add_img_to_target_files.py
+++ b/tools/releasetools/add_img_to_target_files.py
@@ -200,7 +200,7 @@
 
 
 def AddProductServices(output_zip):
-  """Turn the contents of PRODUCT_SERVICES into a product-services image and
+  """Turn the contents of PRODUCT-SERVICES into a product-services image and
   store it in output_zip."""
 
   img = OutputFile(output_zip, OPTIONS.input_tmp, "IMAGES",
@@ -664,7 +664,7 @@
                  os.path.exists(os.path.join(OPTIONS.input_tmp, "IMAGES",
                                              "product.img")))
   has_product_services = (os.path.isdir(os.path.join(OPTIONS.input_tmp,
-                                                     "PRODUCT_SERVICES")) or
+                                                     "PRODUCT-SERVICES")) or
                           os.path.exists(os.path.join(OPTIONS.input_tmp,
                                                       "IMAGES",
                                                       "product-services.img")))