Missing parameter of option() command in cmake file

[mjopenglsdl]

Engine/CMakeLists.txt

Line 16 in 8ed73a4

option(USE_LUA ON)

The command option(USE_LUA ON) would have no effect to the default value (ON),
use option(USE_LUA "some descriptions" ON) instead

Plz take a look at cmake manual:
https://cmake.org/cmake/help/v3.0/command/option.html