mei: bus: do not overflow the device name buffer

1. use strncmp for comparsion strncpy was used for copying
which may omit the final %NUL terminator
2. id->name is statically defined so we can use sizeof

Acked-by: Samuel Ortiz <sameo@linux.intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>