iwlwifi: use correct supported firmware for 6035 and 6000g2

My patch

   iwlwifi: use correct released ucode version

did not correctly report supported firmware
for the 6035 device. This patch fixes it. The
minimum supported firmware version for 6035
is v6.

Also correct the minimum supported firmware
version for the 6000g2 series of devices.

Cc: stable@kernel.org
Signed-off-by: Meenakshi Venkataraman <meenakshi.venkataraman@intel.com>
Reviewed-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>