Assume that <poll.h> is available

* configure.ac (AC_CHECK_HEADERS): Remove poll.h and sys/poll.h.
* pathtrace.c: Include <poll.h> unconditionally.
* stream.c: Likewise.
[HAVE_SYS_POLL_H]: Compile unconditionally.
[!HAVE_SYS_POLL_H]: Remove.

configure.ac

@@ -264,14 +264,12 @@ AC_CHECK_HEADERS(m4_normalize([
 	linux/utsname.h
 	mqueue.h
 	netinet/sctp.h
-	poll.h
 	scsi/sg.h
 	stropts.h
 	sys/conf.h
 	sys/epoll.h
 	sys/fanotify.h
 	sys/ioctl.h
-	sys/poll.h
 	sys/reg.h
 	sys/vfs.h
 	sys/xattr.h

pathtrace.c

@@ -28,11 +28,7 @@
 
 #include "defs.h"
 #include <sys/param.h>
-#if defined HAVE_POLL_H
 #include <poll.h>
-#elif defined HAVE_SYS_POLL_H
-# include <sys/poll.h>
-#endif
 
 #include "syscall.h"
 

stream.c

@@ -27,11 +27,7 @@
  */
 
 #include "defs.h"
-#if defined HAVE_POLL_H
 #include <poll.h>
-#elif defined HAVE_SYS_POLL_H
-# include <sys/poll.h>
-#endif
 #ifdef HAVE_SYS_CONF_H
 # include <sys/conf.h>
 #endif
@@ -156,8 +152,6 @@ SYS_FUNC(getpmsg)
 #endif /* STREAMS syscalls support */
 
 
-#ifdef HAVE_SYS_POLL_H
-
 #include "xlat/pollflags.h"
 
 static int
@@ -319,10 +313,3 @@ SYS_FUNC(ppoll)
 	}
 	return rc;
 }
-
-#else /* !HAVE_SYS_POLL_H */
-SYS_FUNC(poll)
-{
-	return 0;
-}
-#endif