staging: rtl8192e: Remove function ..dm_check_ac_dc_power calling a script

Remove function _rtl92e_dm_check_ac_dc_power calling a script
/etc/acpi/wireless-rtl-ac-dc-power.sh that is not available. This script
is not part of the kernel and it is not available on the www. The result
is that this function is just dead code.

Signed-off-by: Philipp Hortmann <philipp.g.hortmann@gmail.com>
Cc: stable <stable@kernel.org>
Link: https://lore.kernel.org/r/20230228202857.GA16442@matrix-ESPRIMO-P710


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