lua: fix license path for lua 5.2

The file containing the license for lua 5.1 was removed and the license
text was added to the readme in 5.2.

[Peter: swap 5.1/5.2 logic]
Signed-off-by: Frank Hunleth <fhunleth@troodon-software.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

package/lua/lua.mk

@@ -12,7 +12,11 @@ endif
 LUA_SITE = http://www.lua.org/ftp
 LUA_INSTALL_STAGING = YES
 LUA_LICENSE = MIT
+ifeq ($(BR2_PACKAGE_LUA_5_1),y)
 LUA_LICENSE_FILES = COPYRIGHT
+else
+LUA_LICENSE_FILES = doc/readme.html
+endif
 
 LUA_PROVIDES = luainterpreter