iwlwifi: remove unnecessary cfg mangling for Qu C and QuZ with Jf

Now that we identify the correct cfgs with the new tables for Qu step
C and QuZ with Jf, we can remove the mangling we do later on.

Change-Id: Ic01ce67db147e897ad2424f0e05a70a00d2c620e
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>