epoll_create1: fix flags decoding

* xlat/epollflags.in: Remove EPOLL_NONBLOCK, provide fallback definition
for EPOLL_CLOEXEC.
* tests/epoll_create1.c: New file.
* tests/epoll_create1.expected: Likewise.
* tests/epoll_create1.test: New test.
* tests/Makefile.am (check_PROGRAMS): Add epoll_create1.
(TESTS): Add epoll_create1.test.
(EXTRA_DIST): Add epoll_create1.expected.
* tests/.gitignore: Add epoll_create1.
diff --git a/tests/Makefile.am b/tests/Makefile.am
index dc76ddd..180f473 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -11,6 +11,7 @@
 check_PROGRAMS = \
 	bpf \
 	caps \
+	epoll_create1 \
 	eventfd \
 	execve \
 	execveat \
@@ -72,6 +73,7 @@
 	bpf.test \
 	caps.test \
 	dumpio.test \
+	epoll_create1.test \
 	eventfd.test \
 	execve.test \
 	execveat.test \
@@ -131,6 +133,7 @@
 EXTRA_DIST = init.sh run.sh match.awk \
 	     caps.awk \
 	     dumpio.expected \
+	     epoll_create1.expected \
 	     eventfd.expected \
 	     execve.expected \
 	     execve-v.expected \