staging: ks7010: fix warning on return for void functions

This patch fixes the checkpatch warning in ks7010_sdio.c
'void function return statements are not generally useful'

Signed-off-by: Hariharan R <hariharanrangasamy@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>