utils: Add a cpu_count wrapper function

Add a cpu_count wrapper function (useful from annonymous python where
the import would be trickier).

(From OE-Core rev: 0ae27a55759e7c4254e704e18b304d40013cb5c3)

Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/lib/oe/utils.py

@@ -150,3 +150,7 @@ def trim_version(version, num_parts=2):
     parts = version.split(".")
     trimmed = ".".join(parts[:num_parts])
     return trimmed
+
+def cpu_count():
+    import multiprocessing
+    return multiprocessing.cpu_count()