staging: ks7010: invert conditional, reduce indent

Function _ks_wlan_hw_power_save has 5 levels of indentation. Reducing
the amount of indentation may make code clearer to read. Also a number
of other checkpatch warnings may be removed if we first reduce the
level of indentation in this function.

Invert conditional and return from function if new conditional
evaluates to true. Repeat on subsequent conditional. Reduce
indentation without changing the program logic.

Signed-off-by: Tobin C. Harding <me@tobin.cc>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>