erofs: reduntant assignment in __erofs_get_meta_page()

As Joe Perches suggested [1],
 		err = bio_add_page(bio, page, PAGE_SIZE, 0);
-		if (unlikely(err != PAGE_SIZE)) {
+		if (err != PAGE_SIZE) {
 			err = -EFAULT;
 			goto err_out;
 		}

The initial assignment to err is odd as it's not
actually an error value -E<FOO> but a int size
from a unsigned int len.

Here the return is either 0 or PAGE_SIZE.

This would be more legible to me as:

		if (bio_add_page(bio, page, PAGE_SIZE, 0) != PAGE_SIZE) {
			err = -EFAULT;
			goto err_out;
		}

[1] https://lore.kernel.org/r/74c4784319b40deabfbaea92468f7e3ef44f1c96.camel@perches.com/
Signed-off-by: Gao Xiang <gaoxiang25@huawei.com>
Link: https://lore.kernel.org/r/20190829171741.225219-1-gaoxiang25@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

fs/erofs/data.c

@@ -69,8 +69,7 @@ repeat:
 			goto err_out;
 		}
 
-		err = bio_add_page(bio, page, PAGE_SIZE, 0);
-		if (err != PAGE_SIZE) {
+		if (bio_add_page(bio, page, PAGE_SIZE, 0) != PAGE_SIZE) {
 			err = -EFAULT;
 			goto err_out;
 		}