staging: rtl8192e: Remove unused variable bIPSModeBackup

bIPSModeBackup is just once initialized and never used. Remove resulting
dead code.

Signed-off-by: Philipp Hortmann <philipp.g.hortmann@gmail.com>
Link: https://lore.kernel.org/r/657035f84d266fd5c6f96e9b530a96c2ab4ff900.1664616227.git.philipp.g.hortmann@gmail.com


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