Duplicate tags in downloaded mbox

使用 git-pw patch download 982444 重现该问题，并将下载的 mbox 与链接的示例进行比较。跟踪 patch 下载路径，找出重复的 Tags 在哪里被去重。完成标准是保留每一行原始的 Signed-off-by，并添加一个覆盖重复 Tags 的回归测试。

If a comment duplicates tags like Signed-off-by, these are de-duplicated when downloading the mbox. For example

https://patchwork.ozlabs.org/patch/982444/mbox/

<snip>

Following example commands can be used to set the auto-lb params:
ovs-vsctl set open_vswitch . other_config:pmd-auto-lb="true"
ovs-vsctl set open_vswitch . other_config:pmd-auto-lb-thresh="80"
ovs-vsctl set open_vswitch . other_config:pmd-auto-lb-min-improvement="5"
ovs-vsctl set open_vswitch . other_config:pmd-auto-lb-drop-check="true"

Co-authored-by: Rohith Basavaraja <rohith.basavaraja@gmail.com>

Signed-off-by: Nitin Katiyar <nitin.katiyar@ericsson.com>
Signed-off-by: Rohith Basavaraja <rohith.basavaraja@gmail.com>
---
 lib/dpif-netdev.c | 589
+++++++++++++++++++++++++++++++++++++++++++++++++++---
 1 file changed, 561 insertions(+), 28 deletions(-)

<snip>

git-pw patch download 982444 > rfc1-auto-balance.patch
cat !$

<snip>

Following example commands can be used to set the auto-lb params:
ovs-vsctl set open_vswitch . other_config:pmd-auto-lb="true"
ovs-vsctl set open_vswitch . other_config:pmd-auto-lb-thresh="80"
ovs-vsctl set open_vswitch . other_config:pmd-auto-lb-min-improvement="5"
ovs-vsctl set open_vswitch . other_config:pmd-auto-lb-drop-check="true"

Co-authored-by: Rohith Basavaraja <rohith.basavaraja@gmail.com>

Signed-off-by: Nitin Katiyar <nitin.katiyar@ericsson.com>
Signed-off-by: Rohith Basavaraja <rohith.basavaraja@gmail.com>
Signed-off-by: Nitin Katiyar <nitin.katiyar@ericsson.com>
Signed-off-by: Rohith Basavaraja <rohith.basavaraja@gmail.com>
Signed-off-by: Nitin Katiyar <nitin.katiyar@ericsson.com>
Signed-off-by: Rohith Basavaraja <rohith.basavaraja@gmail.com>
---
 lib/dpif-netdev.c | 589
+++++++++++++++++++++++++++++++++++++++++++++++++++---
 1 file changed, 561 insertions(+), 28 deletions(-)

<snip>