egl: android: Dequeue buffer for the next frame soon after enqueuing
Insignificant optimization that helps to reduce input-to-draw latency.
On slow Allwinner A64 SOC this commit helps to save just a ~140uS of frame time. Not much but still it's something.
NOTE: 140uS value assumes !16583 (closed) merged. Without !16583 (closed) value will be much greater.