staging: rtl8723bs: hal: Remove set but unused variable

Removed "delta_IQK" and its occurrences in comments
and code because the variable is set but not used.
Issue detected by GCC.

Signed-off-by: Fabio M. De Francesco <fmdefrancesco@gmail.com>
Link: https://lore.kernel.org/r/20210512073852.14085-1-fmdefrancesco@gmail.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>