Initial work on getting bitbake working under pypy

- use os.chmod, not os.fchmod, as the latter is missing under pypy
- rearrange our imports a bit
- don't die if sqlite3 is missing shared cache support

(Bitbake rev: f229824dc9c453adf6067500e2bf6761536e4f2f)

Signed-off-by: Chris Larson <chris_larson@mentor.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

bitbake/lib/bb/build.py

@@ -224,7 +224,8 @@ def exec_func_shell(function, d, runfile, cwd=None):
         if cwd:
             script.write("cd %s\n" % cwd)
         script.write("%s\n" % function)
-        os.fchmod(script.fileno(), 0775)
+
+    os.chmod(runfile, 0775)
 
     env = {
         'PATH': d.getVar('PATH', True),