mariadb: bump to 10.2.22

From upstream release notes:

- Backport Information Schema CHECK_CONSTRAINTS Table.
- MDEV-17475: Maximum value of table_definition_cache is now 2097152.
- InnoDB ALTER TABLE fixes: MDEV-16499, MDEV-18186, MDEV-18237, MDEV-18222,
  MDEV-18256, MDEV-18016, MDEV-16849
- Mariabackup fixes: MDEV-18185, MDEV-18201, MDEV-18194
- Galera crash recovery fix: MDEV-15740
- Encryption fixes: MDEV-18129, MDEV-18183, MDEV-18279
- Fixes for the following security vulnerabilities:
  - CVE-2019-2510
  - CVE-2019-2537

OpenWrt notes:
- OpenSSL patch dropped as issue fixed upstream

Signed-off-by: Sebastian Kemper <sebastian_ml@gmx.net>

utils/mariadb/Makefile

@@ -8,7 +8,7 @@
 include $(TOPDIR)/rules.mk
 
 PKG_NAME:=mariadb
-PKG_VERSION:=10.2.21
+PKG_VERSION:=10.2.22
 PKG_RELEASE:=1
 
 PKG_SOURCE:=$(PKG_NAME)-$(PKG_VERSION).tar.gz
@@ -18,7 +18,7 @@ PKG_SOURCE_URL := \
 	https://ftp.yz.yamagata-u.ac.jp/pub/dbms/mariadb/$(PKG_NAME)-$(PKG_VERSION)/source \
 	https://downloads.mariadb.org/interstitial/$(PKG_NAME)-$(PKG_VERSION)/source
 
-PKG_HASH:=637f0808b65ec06902897a2f885a60377828d019d35802402dca541f8113536c
+PKG_HASH:=42f4c54c29b7c196bd105bbf4d2ea721f869b14cb7ba436c3566e6dd2760614c
 PKG_MAINTAINER:=Sebastian Kemper <sebastian_ml@gmx.net>
 PKG_LICENSE:=GPL-2.0 LGPL-2.1
 PKG_LICENSE_FILES:=COPYING libmariadb/COPYING.LIB