octeontx2-af: Fix an off by one in rvu_dbg_qsize_write()

This code does not allocate enough memory for the NUL terminator so it
ends up putting it one character beyond the end of the buffer.

Fixes: 8756828a ("octeontx2-af: Add NPA aura and pool contexts to debugfs")
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/ethernet/marvell/octeontx2/af/rvu_debugfs.c

@@ -473,7 +473,7 @@ static ssize_t rvu_dbg_qsize_write(struct file *filp,
 	u16 pcifunc;
 	int ret, lf;
 
-	cmd_buf = memdup_user(buffer, count);
+	cmd_buf = memdup_user(buffer, count + 1);
 	if (IS_ERR(cmd_buf))
 		return -ENOMEM;