Keep reducing jobs on ENOMEM for shmget()

Some platforms return ENOMEM, not just EINVAL, for too large
a size.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
diff --git a/init.c b/init.c
index 4a3716b..8dc5784 100644
--- a/init.c
+++ b/init.c
@@ -255,7 +255,7 @@
 		shm_id = shmget(0, size, IPC_CREAT | 0600);
 		if (shm_id != -1)
 			break;
-		if (errno != EINVAL) {
+		if (errno != EINVAL && errno != ENOMEM) {
 			perror("shmget");
 			break;
 		}