fs: ext4: fix symlink read function

Since last API changes for files >2GB, the read of symlink is broken as
ext4fs_read_file now returns 0 instead of the length of the actual read.

Signed-off-by: Gary Bisson <gary.bisson@boundarydevices.com>

fs/ext4/ext4_common.c

@@ -2046,7 +2046,7 @@ static char *ext4fs_read_symlink(struct ext2fs_node *node)
 		status = ext4fs_read_file(diro, 0,
 					   __le32_to_cpu(diro->inode.size),
 					   symlink, &actread);
-		if (status == 0) {
+		if ((status < 0) || (actread == 0)) {
 			free(symlink);
 			return 0;
 		}