ES: main: refactored rendering loop to be more energy efficient

[faux123]

Description

if no input events are happening, then the rendering loop will render
around 40Hz, if input events are queued, it will render just as before
(which is limited by vsync at 60Hz)

this saves around 25% power drain while screen is off and around 5-8%
power drain while screen is on

Fixes # (issue)

if no input events are happening, then the rendering loop will render
around 40Hz, if input events are queued, it will render just as before
(which is limited by vsync at 60Hz)

this saves around 25% power drain while screen is off and around 5-8%
power drain while screen is on

Type of change

Please delete options that are not relevant.

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)

How Has This Been Tested Locally?

• Test A - load existing pre-patched release, measure the current drain from /sys/class/power_supply/current_avg and note the current drain amount
• Test B - load post patched release, measure the same drain and note the current drain amount

Test Configuration:

• Build OS name and version: latest dev
• Docker (Y/N): N
• Rocknix Branch: dev

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas