drm/amd/display: Fix potential index out of bounds in color transformation function
Fixes index out of bounds issue in the color transformation function.
The issue could occur when the index 'i' exceeds the number of transfer
function points (TRANSFER_FUNC_POINTS).
The fix adds a check to ensure 'i' is within bounds before accessing the
transfer function points. If 'i' is out of bounds, an error message is
logged and the function returns false to indicate an error.