Document vfpu

[dogo]

This PR introduces a set of optimized mathematical functions that leverage the PSP's Vector Floating Point Unit (VFPU) for fast computation of trigonometric operations. The main functions added are:

• oslVfpu_sinf: Calculates the sine of an angle (in radians) multiplied by a radius.
• oslVfpu_cosf: Calculates the cosine of an angle (in radians) multiplied by a radius.

These functions are specifically designed for high performance on the PSP platform, making them ideal for scenarios requiring efficient trigonometric calculations.

Key Features:

• Optimized for PSP: Uses the VFPU, ensuring very fast execution.
• Trigonometric Calculations: Provides sine and cosine functions with support for radians and a scaling radius.
• Doxygen Documentation: The code is fully documented, facilitating easy understanding and maintenance.

This PR is a significant enhancement for projects requiring precise and fast mathematical operations on the PSP, particularly in graphics or physics simulations.