staging: r8188eu: remove dead code for tx power tracking

The odm_TXPowerTrackingCallback_ThermalMeter_8188E contains code
for OFDM paths A and B. It seems that path B is not used, is2t is
always false. Remove resulting dead code.

Without the path B code, the ele_A and ele_C variables are set but
not used. They can be removed. With ele_A and ele_C gone, X and Y
are now set but no longer used. Remove them as well.

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Martin Kaiser <martin@kaiser.cx>
Link: https://lore.kernel.org/r/20220204090941.309900-3-martin@kaiser.cx


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