Configure: support for lua5.2

Close #8339

Patch from ll2 on trac

configure.ac

@@ -1506,6 +1506,11 @@ AC_ARG_ENABLE(lua,
     [disable LUA scripting support (default enabled)])])
 if test "${enable_lua}" != "no"
 then
+  PKG_CHECK_MODULES(LUA, lua5.2,
+    [ have_lua=yes ],
+    [
+    AC_MSG_WARN([${LUA_PKG_ERRORS}, trying lua 5.1 instead])
+
     PKG_CHECK_MODULES(LUA, lua5.1,
       [ have_lua=yes ],
       [
@@ -1518,6 +1523,8 @@ then
           AC_CHECK_HEADERS([lua.h lauxlib.h lualib.h],
             [],
             [ have_lua=no ] )
+          AC_CHECK_LIB(  lua5.2 , luaL_newstate,
+            [LUA_LIBS="-llua5.2"],
           AC_CHECK_LIB( lua5.1 , luaL_newstate,
             [LUA_LIBS="-llua5.1"],
             AC_CHECK_LIB( lua51 , luaL_newstate,
@@ -1526,8 +1533,8 @@ then
                 [LUA_LIBS="-llua"],
                 [ have_lua=no
                 ], [-lm])
-          )
-        )
+            )))
+        ])
       ])
     ])
   if test "x${have_lua}" = "xyes" ;  then