luasql: fix compile with mariadb-10.2.x

This is in anticipation of the mariadb upgrade to 10.2.x. luasql compile
fails:

In file included from src/ls_mysql.c:21:0:
src/ls_mysql.c: In function 'luaopen_luasql_mysql':
src/ls_mysql.c:605:25: error: expected ')' before 'MYSQL_SERVER_VERSION'
     lua_pushliteral (L, MYSQL_SERVER_VERSION);
                         ^
src/ls_mysql.c:605:5: error: too few arguments to function 'lua_pushlstring'
     lua_pushliteral (L, MYSQL_SERVER_VERSION);
     ^
/home/equeiroz/src/openwrt-asus/staging_dir/target-mipsel_74kc_musl/usr/include/lua.h:175:16: note: declared here
 LUA_API void  (lua_pushlstring) (lua_State *L, const char *s, size_t l);
                ^~~~~~~~~~~~~~~

To fix this cherry-pick upstream commit
6df3f672313f8dbca219199c8ec8d20c0247347f.

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

lang/luasql/Makefile

@@ -9,7 +9,7 @@ include $(TOPDIR)/rules.mk
 
 PKG_NAME:=luasql
 PKG_VERSION:=2.3.0
-PKG_RELEASE:=1
+PKG_RELEASE:=2
 
 PKG_SOURCE:=$(PKG_NAME)-$(PKG_VERSION).tar.xz
 PKG_MIRROR_HASH:=b6251065656bf3e066d90d492dd06eec2c2cc76ab4b94187ce3ed9620d41f741

lang/luasql/patches/01-mariadb-compat.patch

@@ -0,0 +1,20 @@
+commit 6df3f672313f8dbca219199c8ec8d20c0247347f
+Author: Tomás Guisasola <tomasguisasola@gmail.com>
+Date:   Mon Jul 31 09:41:49 2017 -0300
+
+    Add support for building with MariaDB (thanks to Florian Weimer).
+
+--- a/src/ls_mysql.c
++++ b/src/ls_mysql.c
+@@ -602,7 +602,11 @@ LUASQL_API int luaopen_luasql_mysql (lua
+ 	luaL_setfuncs(L, driver, 0);
+ 	luasql_set_info (L);
+     lua_pushliteral (L, "_MYSQLVERSION");
++#ifdef MARIADB_CLIENT_VERSION_STR
++    lua_pushliteral (L, MARIADB_CLIENT_VERSION_STR);
++#else
+     lua_pushliteral (L, MYSQL_SERVER_VERSION);
++#endif
+     lua_settable (L, -3);
+ 	return 1;
+ }