poll-h: fix for glibc platforms

[Bruno Haible]

After I wrote a unit test for the 'poll-h' module, I see it fails on glibc
platforms:

test-poll-h.c:28: error: ‘POLLRDNORM’ undeclared here (not in a function)
test-poll-h.c:28: error: ‘POLLRDBAND’ undeclared here (not in a function)
test-poll-h.c:28: error: ‘POLLWRNORM’ undeclared here (not in a function)
test-poll-h.c:28: error: ‘POLLWRBAND’ undeclared here (not in a function)

These macros are defined only when _GNU_SOURCE or similar is defined.
This fixes it:


2010-09-28  Bruno Haible  <address@hidden>

        poll-h: Ensure POLL{RD,WR}{NORM,BAND} are defined on glibc platforms.
        * modules/poll-h (Depends-on): Add 'extensions'.

--- modules/poll-h.orig Wed Sep 29 01:15:35 2010
+++ modules/poll-h      Wed Sep 29 01:05:29 2010
@@ -7,6 +7,7 @@
 
 Depends-on:
 c++defs
+extensions
 warn-on-use
 
 configure.ac: