package/vim: fix build with uclibc

Fix the following build failure with uclibc raised since bump to version
8.2.3565 in commit 5650439b922d020cfad1131e5fb536bce73eb845 and
https://github.com/vim/vim/commit/0a7984af5601323fae7b3398f05a48087db7b767:

In file included from vim.h:27,
                 from fileio.c:14:
fileio.c: In function 'time_differs':
auto/config.h:149:22: error: 'stat_T' {aka 'struct stat'} has no member named 'st_mtim'; did you mean 'st_mtime'?
  149 | #define ST_MTIM_NSEC st_mtim.tv_nsec
      |                      ^~~~~~~

Fixes:
 - http://autobuild.buildroot.org/results/2132f9aa1b0bc618c91f7bf44fbd1b71b9d6ba05

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
(cherry picked from commit 0b518033e2ee0cb38430374c5b3781459d3c61d6)
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

package/vim/0001-Fix-config-of-old-systems-for-nanosecond-resolution-timestamps.patch

@@ -0,0 +1,56 @@
+From b5db1ebf06d2904522ebf246f9c6a8bbf8fca398 Mon Sep 17 00:00:00 2001
+From: Gary Johnson <garyjohn@spocom.com>
+Date: Tue, 26 Oct 2021 13:50:19 -0700
+Subject: [PATCH] Fix config of old systems for nanosecond-resolution
+ timestamps
+
+On old systems (e.g. 32-bit systems running Ubuntu 10.4), defining
+_XOPEN_SOURCE causes _BSD_SOURCE and _SVID_SOURCE not to be defined,
+which causes nanosecond-resolution timestamps not to be included in
+struct stat, which causes the build of fileio.c to fail.
+
+_XOPEN_SOURCE is defined for some systems in vim.h.
+
+A solution is to define _BSD_SOURCE and _SVID_SOURCE whenever
+_XOPEN_SOURCE is defined.
+
+On new systems, defining either _BSD_SOURCE or _SVID_SOURCE causes
+/usr/include/features.h to issue a warning message about _BSD_SOURCE and
+_SVID_SOURCE being deprecated and to use _DEFAULT_SOURCE instead.
+
+A solution for that is to also define _DEFAULT_SOURCE when _BSD_SOURCE
+and _SVID_SOURCE are defined.
+
+[Retrieved from:
+https://github.com/vim/vim/pull/9054/commits/b5db1ebf06d2904522ebf246f9c6a8bbf8fca398]
+Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
+---
+ src/vim.h | 15 +++++++++++++++
+ 1 file changed, 15 insertions(+)
+
+diff --git a/src/vim.h b/src/vim.h
+index 31d4bdefe87..f62ad88c7a1 100644
+--- a/src/vim.h
++++ b/src/vim.h
+@@ -43,6 +43,21 @@
+ // 700 is needed for mkdtemp().
+ #  ifndef _XOPEN_SOURCE
+ #   define _XOPEN_SOURCE    700
++
++// On old systems, defining _XOPEN_SOURCE causes _BSD_SOURCE and/or
++// _SVID_SOURCE not to be defined, so do that here.  Those are needed to
++// include nanosecond-resolution timestamps in struct stat.  On new systems,
++// _DEFAULT_SOURCE is needed to avoid warning messages about using deprecated
++// _BSD_SOURCE or _SVID_SOURCE.
++#   ifndef _BSD_SOURCE
++#    define _BSD_SOURCE 1
++#   endif
++#   ifndef _SVID_SOURCE
++#    define _SVID_SOURCE 1
++#   endif
++#   ifndef _DEFAULT_SOURCE
++#    define _DEFAULT_SOURCE 1
++#   endif
+ #  endif
+ # endif
+