[NaCl SDK]: use standard __BEGIN_DECLS macros in sys/select.h

[NaCl SDK]: use standard __BEGIN_DECLS macros in sys/select.h

There is no reason for sys/select.h to depend on
sdk_util headers.  The __BEGIN_DECLS/__END_DECLS
macros are available in all our toolchains.

This was causing various problems in the naclports
repo.

Committed: https://crrev.com/e783a653f8005459e1bc5e26fc570ed8d205c384
Cr-Commit-Position: refs/heads/master@{#294044}

[Sam Clegg, 2014-09-04 21:27:22]

sbc@chromium.org changed reviewers:
+ bradnelson@chromium.org, noelallen@chromium.org

[bradn, 2014-09-04 22:55:52]

bradnelson@google.com changed reviewers:
+ bradnelson@google.com

[bradn, 2014-09-04 22:55:52]

lgtm

[Sam Clegg, 2014-09-09 22:45:48]

The CQ bit was checked by sbc@chromium.org

[commit-bot: I haz the power, 2014-09-09 23:06:05]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/sbc@chromium.org/539163004/20001

[commit-bot: I haz the power, 2014-09-10 00:10:30]

Committed patchset #2 (id:20001) as bffa44509b38b18c2aa0c678425e84aee63cb003

[commit-bot: I haz the power, 2014-09-10 03:56:46]

Patchset 2 (id:??) landed as
https://crrev.com/e783a653f8005459e1bc5e26fc570ed8d205c384
Cr-Commit-Position: refs/heads/master@{#294044}