scripts: west_commands: Add powershell autocompletion (west -b)

Windows powershell can by default not autocomplete known boards when
tapping which can cause frustration when you can't quite remember the
exact name or you don't want to type it out.
west build .\path\to\application\ -p -b stm<tab> will search for
available board including 'stm' in their name.

Signed-off-by: Tais Hjortshøj <[email protected]>

Author: Tais Hjortshøj

doc/develop/west/install.rst

@@ -53,6 +53,7 @@ West currently supports shell completion in the following shells:
 * bash
 * zsh
 * fish
+* powershell (board qualifiers only)
 
 In order to enable shell completion, you will need to obtain the corresponding
 completion script and have it sourced.
@@ -102,5 +103,22 @@ Using the completion scripts:
 
       west completion fish > $HOME/.config/fish/completions/west.fish
 
+  .. group-tab:: powershell
+
+    *One-time setup*:
+
+    .. code-block:: powershell
+
+      west completion powershell | Out-String | Invoke-Expression
+
+    *Permanent setup*:
+
+    .. code-block:: powershell
+
+      Set-ExecutionPolicy RemoteSigned -Scope CurrentUser
+      New-item -type file -force $PROFILE
+      west completion powershell > $HOME/west-completion.ps1
+      (Add-Content -Path $PROFILE -Value ". '{$HOME/west-completion.ps1}'")
+
 .. _PyPI:
    https://pypi.org/project/west/

doc/develop/west/zephyr-cmds.rst

@@ -40,6 +40,7 @@ It currently supports the following shells:
 - bash
 - zsh
 - fish
+- powershell (board qualifiers only)
 
 Additional instructions are available in the command's help::