qemu: add patch for qga guest-shutdown command

Corresponds to commit 33bbecea in master branch

Ref: https://github.com/openwrt/packages/issues/14244
Signed-off-by: Yousong Zhou <yszhou4tech@gmail.com>

utils/qemu/patches/0001-configure-allow-disable-fortify_source.patch

@@ -1,7 +1,7 @@
-From cbb0971d0d1bc32413095810e24f17eb7169810a Mon Sep 17 00:00:00 2001
+From 8b0920febc7f831895e592a1328471696ed271c5 Mon Sep 17 00:00:00 2001
 From: Yousong Zhou <yszhou4tech@gmail.com>
 Date: Sat, 24 Feb 2018 13:43:19 +0800
-Subject: [PATCH 1/4] configure: allow disable fortify_source
+Subject: [PATCH] configure: allow disable fortify_source
 
 Tell build system of qemu to not add _FORTIFY_SOURCE options and let the
 OpenWrt base build system decide flavor of fortify_source to use

utils/qemu/patches/0002-configure-allow-enabling-disabling-libudev-from-comm.patch

@@ -1,8 +1,7 @@
-From 39b07d1742475f2c60ae2c80f3f2853bb556e0b1 Mon Sep 17 00:00:00 2001
+From acd47f780447c0c3f528e1530ad76267abba5661 Mon Sep 17 00:00:00 2001
 From: Yousong Zhou <yszhou4tech@gmail.com>
 Date: Tue, 2 Apr 2019 06:31:31 +0000
-Subject: [PATCH 2/4] configure: allow enabling/disabling libudev from command
+Subject: [PATCH] configure: allow enabling/disabling libudev from command line
- line
 
 ---
  configure | 4 ++++

utils/qemu/patches/0003-disas-fix-compilation-failure-when-isnan-is-a-macro.patch

@@ -1,7 +1,7 @@
-From fb90eacb808c3b1719d6a5f2deefe88c82589bfb Mon Sep 17 00:00:00 2001
+From be686d9ea58f8fba22428f4cd79e72590fad8b05 Mon Sep 17 00:00:00 2001
 From: Yousong Zhou <yszhou4tech@gmail.com>
 Date: Sat, 24 Feb 2018 13:45:25 +0800
-Subject: [PATCH 3/4] disas: fix compilation failure when isnan is a macro
+Subject: [PATCH] disas: fix compilation failure when isnan is a macro
 
 ---
  disas/libvixl/vixl/utils.h | 16 +++++++++++-----

utils/qemu/patches/0004-pc-bios-fix-compilation-when-AS-is-actually-gcc-driv.patch

@@ -1,8 +1,7 @@
-From 8cff6a5f07f66103809e6bf4a26c512d70ab2841 Mon Sep 17 00:00:00 2001
+From bbf909a0b47efcfc999306e8304feaa26796f55c Mon Sep 17 00:00:00 2001
 From: Yousong Zhou <yszhou4tech@gmail.com>
 Date: Sat, 24 Feb 2018 13:46:31 +0800
-Subject: [PATCH 4/4] pc-bios: fix compilation when $(AS) is actually gcc
+Subject: [PATCH] pc-bios: fix compilation when $(AS) is actually gcc driver
- driver
 
 ---
  pc-bios/optionrom/Makefile | 4 ++--

utils/qemu/patches/0005-qga-invoke-separate-applets-for-guest-shutdown-modes.patch

@@ -0,0 +1,47 @@
+From dd2c81be56d3191cc39a5f99fab59008abc42245 Mon Sep 17 00:00:00 2001
+From: Yousong Zhou <yszhou4tech@gmail.com>
+Date: Thu, 17 Dec 2020 15:55:55 +0800
+Subject: [PATCH] qga: invoke separate applets for guest-shutdown modes
+
+/sbin/shutdown is not available on OpenWrt by default
+
+Origin: "main/qemu: fix shutdown from guest agent"
+https://gitlab.alpinelinux.org/alpine/aports/commit/76b81b486480fd9c3294cd420bcf2df01c27790d
+---
+ qga/commands-posix.c | 5 +++++
+ 1 file changed, 5 insertions(+)
+
+diff --git a/qga/commands-posix.c b/qga/commands-posix.c
+index 7ee6a33cce..22a22317a6 100644
+--- a/qga/commands-posix.c
++++ b/qga/commands-posix.c
+@@ -82,6 +82,7 @@ static void ga_wait_child(pid_t pid, int *status, Error **errp)
+ void qmp_guest_shutdown(bool has_mode, const char *mode, Error **errp)
+ {
+     const char *shutdown_flag;
++    const char *fallback_cmd = NULL;
+     Error *local_err = NULL;
+     pid_t pid;
+     int status;
+@@ -89,10 +90,13 @@ void qmp_guest_shutdown(bool has_mode, const char *mode, Error **errp)
+     slog("guest-shutdown called, mode: %s", mode);
+     if (!has_mode || strcmp(mode, "powerdown") == 0) {
+         shutdown_flag = "-P";
++        fallback_cmd = "/sbin/poweroff";
+     } else if (strcmp(mode, "halt") == 0) {
+         shutdown_flag = "-H";
++        fallback_cmd = "/sbin/halt";
+     } else if (strcmp(mode, "reboot") == 0) {
+         shutdown_flag = "-r";
++        fallback_cmd = "/sbin/reboot";
+     } else {
+         error_setg(errp,
+                    "mode is invalid (valid values are: halt|powerdown|reboot");
+@@ -109,6 +113,7 @@ void qmp_guest_shutdown(bool has_mode, const char *mode, Error **errp)
+ 
+         execle("/sbin/shutdown", "shutdown", "-h", shutdown_flag, "+0",
+                "hypervisor initiated shutdown", (char*)NULL, environ);
++        execle(fallback_cmd, fallback_cmd, (char*)NULL, environ);
+         _exit(EXIT_FAILURE);
+     } else if (pid < 0) {
+         error_setg_errno(errp, errno, "failed to create child process");