Revert "mei: Avoid the use of one-element arrays"

This reverts commit 3c3b7dde, as it
turns out Tomas made a better series of patches for this same issue.

Cc: Gustavo A. R. Silva <gustavoars@kernel.org>
Cc: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>