staging: rts5208: fix style warnings in sd.c

This patch fixes the following checkpatch.pl warning in sd.c:
WARNING: else is not generally useful after a break or return

It also makes code more uniform with the new changes

Signed-off-by: Sergio Paracuellos <sergio.paracuellos@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>