Increase dSOL yield with priority fees

[Azrangar]

Inspired by jupSOL, the drift validator can send a portion of the priority fees back to dSOL, increasing the yield.

This can be done in two approaches.

1. Send the pure vanilla SOL from priority fees back to dSOL.

Or

2. Following bonkSOL, use a portion of the priority fees to buyback $DRIFT and distribute to dSOL holders as yield.

The latter would diverse the yield, though $DRIFT would be correlated with SOL but may have higher upside potential due to smaller mcap and growth potential.