tpm_crb: use __le64 annotated variable for response buffer address

use __le64 annotated variable for response buffer address as this is
read in little endian format form the register.

This suppresses sparse warning
drivers/char/tpm/tpm_crb.c:558:18: warning: cast to restricted __le64

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Tested-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>