Add multiprocessing.cpu_count access to platform module.

recipe_modules/platform/test_api.py

Index: recipe_modules/platform/test_api.py
diff --git a/recipe_modules/platform/test_api.py b/recipe_modules/platform/test_api.py
index becd767c4074dbe9e310b304d99e0a3224eada6e..934b0bbf552b323736185b618d68def25806c3f5 100644
--- a/recipe_modules/platform/test_api.py
+++ b/recipe_modules/platform/test_api.py
@@ -17,6 +17,13 @@ class PlatformTestApi(recipe_test_api.RecipeTestApi):
     assert bits in (32, 64)
     return bits
 
+  @recipe_test_api.mod_test_data
+  @staticmethod
+  def cpu_count(cpu_count):
+    assert isinstance(cpu_count, int)
+    assert cpu_count > 0
+    return cpu_count
+
   def __call__(self, name, bits):
     return self.name(name) + self.bits(bits)