games/julius: fix build with SDL 2.0.10

SDL 2.0.10 removed SDL_HINT_ANDROID_SEPARATE_MOUSE_AND_TOUCH and introduced SDL_HINT_MOUSE_TOUCH_EVENTS and SDL_HINT_TOUCH_MOUSE_EVENTS.

Approved by: tcberner (mentor)
Differential Revision: https://reviews.freebsd.org/D21148