cli: fix possible uninitialized read

On Android:

../../modules/control/cli/cli.c:335:9: warning: variable 'ret' is
        used uninitialized whenever 'if' condition is false
        [-Wsometimes-uninitialized]
    if (count > 0)
        ^~~~~~~~~
../../modules/control/cli/cli.c:359:12: note: uninitialized uses
        occurs here
    return ret;
           ^~~