patches/buildroot: fix buffering issue with lldpcli

If you call lldpcli from a program, stdout will be fully buffered, and
we won't get back the result of "show neighbors" (nor anything else).
Expectedly, stderr messages are delivered immediately.

You can verify this by running "cat | lldpcli", give comamnds and
then exit with ctrl-D (EOF).

Signed-off-by: Alessandro Rubini <rubini@gnudd.com>

patches/buildroot/0012-package-lldp-add-fflush-in-lldpcli.patch

+From 0175432f629684a5207e3427cbb4f28a67ed592a Mon Sep 17 00:00:00 2001
+From: Alessandro Rubini <rubini@gnudd.com>
+Date: Thu, 5 Dec 2019 00:30:30 +0100
+Subject: [PATCH] package/lldp: add fflush() in lldpcli
+
+Signed-off-by: Alessandro Rubini <rubini@gnudd.com>
+---
+ ...li-flush-stdout-after-executing-a-command.patch | 25 ++++++++++++++++++++++
+ 1 file changed, 25 insertions(+)
+ create mode 100644 package/lldpd/0003-lldpcli-flush-stdout-after-executing-a-command.patch
+
+diff --git a/package/lldpd/0003-lldpcli-flush-stdout-after-executing-a-command.patch b/package/lldpd/0003-lldpcli-flush-stdout-after-executing-a-command.patch
+new file mode 100644
+index 0000000..0afd271
+--- /dev/null
++++ b/package/lldpd/0003-lldpcli-flush-stdout-after-executing-a-command.patch
+@@ -0,0 +1,25 @@
++From 3849e680b9498c3b5bcefc293bebd36be5ffeec3 Mon Sep 17 00:00:00 2001
++From: Alessandro Rubini <rubini@gnudd.com>
++Date: Sun, 10 Nov 2019 23:16:43 +0100
++Subject: [PATCH] lldpcli: flush stdout after executing a command
++
++Signed-off-by: Alessandro Rubini <rubini@gnudd.com>
++---
++ src/client/lldpcli.c |    1 +
++ 1 files changed, 1 insertions(+), 0 deletions(-)
++
++diff --git a/src/client/lldpcli.c b/src/client/lldpcli.c
++index e534343..85a6ee9 100644
++--- a/src/client/lldpcli.c
+++++ b/src/client/lldpcli.c
++@@ -583,6 +583,7 @@ main(int argc, char *argv[])
++ 	do {
++ 		if ((line = readline(prompt()))) {
++ 			int n = parse_and_exec(conn, fmt, line);
+++			fflush(stdout);
++ 			if (n != 0) {
++ #ifdef HAVE_READLINE_HISTORY
++ 				add_history(line);
++-- 
++1.7.7.2
++
+-- 
+2.1.4
+