lantiq: remove read-only flag on two partitions on BTHOMEHUBV3A

Remove read-only flag on two partitions on BTHOMEHUBV3A:
  uboot-config - otherwise fw_setenv command cannot be used.
  ath9k-cal    - so that ath9k calibration data can be copied
                 to the partition on a newly installed board.

Signed-off-by: Ben Mulvihill <ben.mulvihill@gmail.com>

SVN-Revision: 49250