staging: rtl8712: Fix indent coding style issue

This patch fixes an indentation coding style issue found by
checkpatch.pl:

WARNING: suspect code indent for conditional statements (16, 32)

Signed-off-by: Mihaela Muraru <mihaela.muraru21@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>