MIPS: Clear the correct flag in sysmips(MIPS_FIXADE, ...).

The sysmips(MIPS_FIXADE, ...) case contains an obvious copy-and-paste
error in the handling of the TIF_LOGADE flag. Fix that

Patchwork: https://patchwork.linux-mips.org/patch/1997/


Signed-off-by: Ralf Baechle <ralf@linux-mips.org>