patch 8.1.0957: Mac: fsync fails on network share

Problem:    Mac: fsync fails on network share.
Solution:   Check for ENOTSUP. (Yee Cheng Chin, closes #4016)
diff --git a/src/fileio.c b/src/fileio.c
index 841de1c..ab2c3fd 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)
+    if (r != 0 && (errno == ENOTTY || errno == ENOTSUP))
 # endif
 	r = fsync(fd);
     return r;
diff --git a/src/version.c b/src/version.c
index b705463..5a3a53c 100644
--- a/src/version.c
+++ b/src/version.c
@@ -780,6 +780,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    957,
+/**/
     956,
 /**/
     955,