Don't try to use -MMD / .o.d depfiles for ninja with .s files.

test/ninja/s-needs-no-depfiles/s-needs-no-depfiles.gyp

Index: test/ninja/s-needs-no-depfiles/s-needs-no-depfiles.gyp
diff --git a/test/dependencies/double_dependent.gyp b/test/ninja/s-needs-no-depfiles/s-needs-no-depfiles.gyp
similarity index 67%
copy from test/dependencies/double_dependent.gyp
copy to test/ninja/s-needs-no-depfiles/s-needs-no-depfiles.gyp
index 334caff723ce8e2722e5a07c129e3658d04543b1..bd66b1a70a82c34199bf80439ce25be2451c6bf5 100644
--- a/test/dependencies/double_dependent.gyp
+++ b/test/ninja/s-needs-no-depfiles/s-needs-no-depfiles.gyp
@@ -5,8 +5,9 @@
 {
   'targets': [
     {
-      'target_name': 'double_dependent',
-      'type': 'none',
+      'target_name': 'empty',
+      'type': 'shared_library',
+      'sources': [ 'empty.s' ],
     },
   ],
 }