Remove wrong poll.h include

musl reports:

warning redirecting incorrect #include <sys/poll.h> to <poll.h>

Signed-off-by: Rosen Penev <rosenp@gmail.com>
Acked-by: Gert Doering <gert@greenie.muc.de>
Message-Id: <20190403225740.8285-1-rosenp@gmail.com>
URL: https://www.mail-archive.com/openvpn-devel@lists.sourceforge.net/msg18336.html
Signed-off-by: Gert Doering <gert@greenie.muc.de>

configure.ac

@@ -436,7 +436,7 @@ AC_CHECK_HEADERS([ \
 	unistd.h signal.h libgen.h stropts.h \
 	syslog.h pwd.h grp.h \
 	sys/sockio.h sys/uio.h linux/sockios.h \
-	linux/types.h sys/poll.h sys/epoll.h err.h \
+	linux/types.h poll.h sys/epoll.h err.h \
 ])
 
 SOCKET_INCLUDES="

src/openvpn/syshead.h

@@ -179,8 +179,8 @@
 #include <resolv.h>
 #endif
 
-#ifdef HAVE_SYS_POLL_H
-#include <sys/poll.h>
+#ifdef HAVE_POLL_H
+#include <poll.h>
 #endif
 
 #ifdef HAVE_SYS_EPOLL_H