meson: drop redundant messages

shell-completion/bash/meson.build

@@ -8,8 +8,6 @@ if bashcompletiondir == ''
         else
                 bashcompletiondir = join_paths(datadir, 'bash-completion/completions')
         endif
-
-        message('bash completions: @0@'.format(bashcompletiondir))
 endif
 
 if bashcompletiondir != 'no'

shell-completion/zsh/meson.build

@@ -3,8 +3,6 @@
 zshcompletiondir = get_option('zshcompletiondir')
 if zshcompletiondir == ''
         zshcompletiondir = join_paths(datadir, 'zsh/site-functions')
-
-        message('zsh completions: @0@'.format(zshcompletiondir))
 endif
 
 if zshcompletiondir != 'no'