Fix bikes breaking when their steering lock is set to zero

[TheCrazy17]

Summary

Sets the bike steer and lean ratios to zero when a vehicle's steeringLock handling is zero, instead of dividing by it.

Motivation

Resolves #494. CBike::ProcessControl divides the steer angle by the steering lock in radians to get a ratio. The steer angle is itself the steering lock times the input, so a lock of zero makes this 0 / 0, a NaN rather than an infinity. Cars survive the same division because an infinity trips their "greater than 1" clamp, while a NaN compares false against every clamp and passes straight through. It reaches the rider lean angle, and CBike::CalculateLeanMatrix builds the bike and rider matrices from it, stretching the ped until respawn.

Test plan

Repro from the issue:

setVehicleHandling(getRandomPlayer().vehicle, "steeringLock", 0)

Get an NRG-500, set its steeringLock to 0, and crash into something. Before this change the ped stretches out and stays broken until respawn. After it, the bike behaves like a normal collision.

Also checked that bikes with a normal steering lock still steer and lean correctly, since only the zero case takes the new path.

Checklist

• Your code should follow the coding guidelines (https://wiki.multitheftauto.com/index.php?title=Coding_guidelines).
• Smaller pull requests are easier to review. If your pull request is beefy, your pull request should be reviewable commit-by-commit.

[FileEX]

Please resolve conflicts & fix build

[TheCrazy17]

Please resolve conflicts & fix build

Done ✅

[FileEX]

It looks like you don't need to preserve this register, since it's modified at 0x6BAC22 anyway

[FileEX]

It looks like you don't need to preserve this register, since it's modified at 0x6BBAE2.