Rename --no-display to --no-mirror

The option impacts both video and audio playback, so "no display" is not
an appropriate name.

PR #3978 <https://github.com/Genymobile/scrcpy/pull/3978>

app/data/zsh-completion/_scrcpy

@@ -39,7 +39,7 @@ arguments=(
     '--no-clipboard-autosync[Disable automatic clipboard synchronization]'
     '--no-downsize-on-error[Disable lowering definition on MediaCodec error]'
     {-n,--no-control}'[Disable device control \(mirror the device in read only\)]'
-    {-N,--no-display}'[Do not display device \(during screen recording or when V4L2 sink is enabled\)]'
+    {-N,--no-mirror}'[Do not mirror device \(only when recording or V4L2 sink is enabled\)]'
     '--no-key-repeat[Do not forward repeated key events when a key is held down]'
     '--no-mipmaps[Disable the generation of mipmaps]'
     '--no-power-on[Do not power on the device on start]'