remove empty vim-powerline
remove empty vim-powerline

Signed-off-by: Zhang Wei <d6fa6f3f4186ada68220f9e69e7ddc7f2c936bdf@lambdacloud.com>

wezhang/vim-setup,wezhang/vim-setup,wezhang/vim-setup,wezhang/vim-setup,wezhang/vim-setup,wezhang/vim-setup