mei: bus-fixup: fix buffer type

The __mei_cl_recv and __mei_cl_send accepts u8 buffer.
Fix buffer type from char to u8.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Link: https://lore.kernel.org/r/20230522101210.2207395-2-tomas.winkler@intel.com


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