infiniband: hfi1: fix a memory leak bug

In fault_opcodes_read(), 'data' is not deallocated if debugfs_file_get()
fails, leading to a memory leak. To fix this bug, introduce the 'free_data'
label to free 'data' before returning the error.
Signed-off-by: Wenwen Wang <wenwen@cs.uga.edu>
Reviewed-by: Leon Romanovsky <leonro@mellanox.com>
Acked-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Link: https://lore.kernel.org/r/1566156571-4335-1-git-send-email-wenwen@cs.uga.eduSigned-off-by: Doug Ledford <dledford@redhat.com>

drivers/infiniband/hw/hfi1/fault.c

@@ -214,7 +214,7 @@ static ssize_t fault_opcodes_read(struct file *file, char __user *buf,
 		return -ENOMEM;
 	ret = debugfs_file_get(file->f_path.dentry);
 	if (unlikely(ret))
-		return ret;
+		goto free_data;
 	bit = find_first_bit(fault->opcodes, bitsize);
 	while (bit < bitsize) {
 		zero = find_next_zero_bit(fault->opcodes, bitsize, bit);
@@ -232,6 +232,7 @@ static ssize_t fault_opcodes_read(struct file *file, char __user *buf,
 	data[size - 1] = '\n';
 	data[size] = '\0';
 	ret = simple_read_from_buffer(buf, len, pos, data, size);
+free_data:
 	kfree(data);
 	return ret;
 }