Handle --clean[-all] directly in emacs-build.cmd

emacs-build.cmd

@@ -1,10 +1,20 @@
 @echo off
 if x%1 == x goto default
+if %1 == --clean goto clean
+if %1 == --clean-all goto cleanall
 if %1==--help goto help
 if %1==-h goto help
 if %1==-? goto help
 goto run
 
+:cleanall
+cd %~dp0 && for %%i in (git build zips pkg) do if exist %%i rmdir /S /Q %%i
+goto:eof
+
+:clean
+cd %~dp0 && for %%i in (build pkg) do if exist %%i rmdir /S /Q %%i
+goto:eof
+
 :default
 emacs-build.cmd --clone --deps --build --pack-emacs --pdf-tools --mu --isync --hunspell --pack-all
 goto:eof