patch 8.1.0961: Mac: fsync may fail sometimes

Problem:    Mac: fsync may fail sometimes.
Solution:   Do not check errno. (Yee Cheng Chin, closes #4025)
diff --git a/src/fileio.c b/src/fileio.c
index ab2c3fd..4060f69 100644
--- a/src/fileio.c
+++ b/src/fileio.c
@@ -5135,7 +5135,7 @@
 
 # ifdef MACOS_X
     r = fcntl(fd, F_FULLFSYNC);
-    if (r != 0 && (errno == ENOTTY || errno == ENOTSUP))
+    if (r != 0)  // F_FULLFSYNC not working or not supported
 # endif
 	r = fsync(fd);
     return r;