staging: greybus: correct typo in comment

Correct a spelling typo from 'Atleast' to 'At least' in comment.
Issue found by checkpatch.

Reviewed-by: Alex Elder <elder@linaro.org>
Signed-off-by: Jaehee Park <jhpark1013@gmail.com>
Link: https://lore.kernel.org/r/2feb03de97ca4dbd27c22cf40f8e185f7dfaae29.1649824370.git.jhpark1013@gmail.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>