The only device using the ATH10K_PACKAGES_IPQ40XX variable in
ipq40xx-mikrotik (the MikroTik hAP ac2) has little RAM and is
using ath10k-ct-smallbuffers by default at the moment. This is
just a suggestion to rename the variable in-case the wifi driver
ever has to be replaced by ath10k.

Analogue to 4a00b8ae

Signed-off-by: Felix Baumann <felix.bau@gmx.de>