staging: rtl8192e: Remove unchanged variable dig_algorithm

staging: rtl8192e: Remove unchanged variable dig_algorithm

Remove variable dig_algorithm as its value is set to DIG_ALGO_BY_RSSI at
initialization. No further writes to dig_algorithm are done. The
equations result accordingly. Remove dead code.

Signed-off-by: Philipp Hortmann <philipp.g.hortmann@gmail.com>
Reviewed-by: Dan Carpenter <dan.carpenter@linaro.org>
Link: https://lore.kernel.org/r/66f7275aa46e68577cc4c20582ffbd16de13f470.1697127817.git.philipp.g.hortmann@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>