kernel: remove upstreamed patch from 4.19

This patch applies cleanly, so it doesn't cause errors while rebasing
patches. It results in redifinition of inode_still_linked, causing build
to fail when ubifs is enabled. Drop the patch.

Fixes: a37098a2d0 ("kernel: bump 4.19 to 4.19.16")
Reported-by: Deng Qingfang <dengqf6@mail2.sysu.edu.cn>
Signed-off-by: Stijn Tintel <stijn@linux-ipv6.be>

target/linux/generic/backport-4.19/500-ubifs-Handle-re-linking-of-inodes-correctly-while-re.patch

@@ -1,89 +0,0 @@
-From: Richard Weinberger <richard@nod.at>
-Date: Wed, 7 Nov 2018 23:04:43 +0100
-Subject: [PATCH] ubifs: Handle re-linking of inodes correctly while recovery
-MIME-Version: 1.0
-Content-Type: text/plain; charset=UTF-8
-Content-Transfer-Encoding: 8bit
-
-UBIFS's recovery code strictly assumes that a deleted inode will never
-come back, therefore it removes all data which belongs to that inode
-as soon it faces an inode with link count 0 in the replay list.
-Before O_TMPFILE this assumption was perfectly fine. With O_TMPFILE
-it can lead to data loss upon a power-cut.
-
-Consider a journal with entries like:
-0: inode X (nlink = 0) /* O_TMPFILE was created */
-1: data for inode X /* Someone writes to the temp file */
-2: inode X (nlink = 0) /* inode was changed, xattr, chmod, … */
-3: inode X (nlink = 1) /* inode was re-linked via linkat() */
-
-Upon replay of entry #2 UBIFS will drop all data that belongs to inode X,
-this will lead to an empty file after mounting.
-
-As solution for this problem, scan the replay list for a re-link entry
-before dropping data.
-
-Fixes: 474b93704f32 ("ubifs: Implement O_TMPFILE")
-Cc: stable@vger.kernel.org
-Cc: Russell Senior <russell@personaltelco.net>
-Cc: Rafał Miłecki <zajec5@gmail.com>
-Reported-by: Russell Senior <russell@personaltelco.net>
-Reported-by: Rafał Miłecki <zajec5@gmail.com>
-Signed-off-by: Richard Weinberger <richard@nod.at>
----
- fs/ubifs/replay.c | 37 +++++++++++++++++++++++++++++++++++++
- 1 file changed, 37 insertions(+)
-
---- a/fs/ubifs/replay.c
-+++ b/fs/ubifs/replay.c
-@@ -242,6 +242,38 @@ static bool inode_still_linked(struct ub
- }
- 
- /**
-+ * inode_still_linked - check whether inode in question will be re-linked.
-+ * @c: UBIFS file-system description object
-+ * @rino: replay entry to test
-+ *
-+ * O_TMPFILE files can be re-linked, this means link count goes from 0 to 1.
-+ * This case needs special care, otherwise all references to the inode will
-+ * be removed upon the first replay entry of an inode with link count 0
-+ * is found.
-+ */
-+static bool inode_still_linked(struct ubifs_info *c, struct replay_entry *rino)
-+{
-+	struct replay_entry *r;
-+
-+	ubifs_assert(c, rino->deletion);
-+	ubifs_assert(c, key_type(c, &rino->key) == UBIFS_INO_KEY);
-+
-+	/*
-+	 * Find the most recent entry for the inode behind @rino and check
-+	 * whether it is a deletion.
-+	 */
-+	list_for_each_entry_reverse(r, &c->replay_list, list) {
-+		ubifs_assert(c, r->sqnum >= rino->sqnum);
-+		if (key_inum(c, &r->key) == key_inum(c, &rino->key))
-+			return r->deletion == 0;
-+
-+	}
-+
-+	ubifs_assert(c, 0);
-+	return false;
-+}
-+
-+/**
-  * apply_replay_entry - apply a replay entry to the TNC.
-  * @c: UBIFS file-system description object
-  * @r: replay entry to apply
-@@ -270,6 +302,11 @@ static int apply_replay_entry(struct ubi
- 
- 				if (inode_still_linked(c, r)) {
- 					err = 0;
-+					break;
-+				}
-+
-+				if (inode_still_linked(c, r)) {
-+					err = 0;
- 					break;
- 				}
-