lara: fix TR2 style walk-run-jump

[lahm86]

Resolves #934.

Checklist

• I have read the coding conventions
• I have added a changelog entry about what my pull request accomplishes, or it is an internal change

Description

This is the specific sequence to break walk-jun-jump.

1. Enter Lara_State_Run; m_JumpPermitted is set to false
2. Interrupt LA_RUN (anim 0) by rolling, for example; m_JumpPermitted is still false
3. Enter Lara_State_Walk and release walk. The state changes here will link to WALK_TO_RUN_RIGHT (anim 4) or WALK_TO_RUN_LEFT (anim 5), depending on the frame.
4. These interim animations link directly to LA_RUN (0), but link to frame 8 or 19. Their state IDs are the same as walk, so control remains in Lara_State_Walk until the state change is processed.
5. m_JumpPermitted will remain false until the frame cycles round again to LF_JUMP_READY (4) - so 18 frames have to play out for WALK_TO_RUN_RIGHT or 7 frames for WALK_TO_RUN_LEFT.

The fix is to set m_JumpPermitted to true at step 3 above when walk is released. For any other situation, Lara will enter LA_RUN again from scratch, so the normal lock check will play out.