misc: xilinx_sdfec: Fix a couple small information leaks

These structs have holes in them so we end up disclosing a few bytes of
uninitialized stack data.

drivers/misc/xilinx_sdfec.c:305 xsdfec_get_status() warn: check that 'status' doesn't leak information (struct has a hole after 'activity')
drivers/misc/xilinx_sdfec.c:449 xsdfec_get_turbo() warn: check that 'turbo_params' doesn't leak information (struct has a hole after 'scale')

We need to zero out the holes with memset().

Fixes: 6bd6a690 ("misc: xilinx_sdfec: Add stats & status ioctls")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Dragan Cvetic <dragan.cvetic@xilinx.com>
Reviewed-by: Michal Simek <michal.simek@xilinx.com>
Link: https://lore.kernel.org/r/20190821070606.GA26957@mwandaSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/misc/xilinx_sdfec.c

@@ -295,6 +295,7 @@ static int xsdfec_get_status(struct xsdfec_dev *xsdfec, void __user *arg)
 	struct xsdfec_status status;
 	int err;
 
+	memset(&status, 0, sizeof(status));
 	spin_lock_irqsave(&xsdfec->error_data_lock, xsdfec->flags);
 	status.state = xsdfec->state;
 	xsdfec->state_updated = false;
@@ -440,6 +441,7 @@ static int xsdfec_get_turbo(struct xsdfec_dev *xsdfec, void __user *arg)
 	if (xsdfec->config.code == XSDFEC_LDPC_CODE)
 		return -EIO;
 
+	memset(&turbo_params, 0, sizeof(turbo_params));
 	reg_value = xsdfec_regread(xsdfec, XSDFEC_TURBO_ADDR);
 
 	turbo_params.scale = (reg_value & XSDFEC_TURBO_SCALE_MASK) >>