How to use single social icon with svg sprite without include the whole Font Awesome icon set

Create a file named sprite.svg

<svg>
	<symbol id="fb-icon" viewbox="-20 -20 200 200">
		<path fill="white" d="M91.84,71.34l3.37-21.99h-21.1V35.08c0-6.02,2.95-11.88,12.4-11.88h9.59V4.49c0,0-8.7-1.49-17.03-1.49	C61.7,3,50.35,13.53,50.35,32.59v16.76H31.04v21.99h19.31v53.15h23.77V71.34H91.84z"/></path>
	</symbol>
</svg>

Paste this in functions.php

function add_image_sprite_map(){
    include('assets/images/sprite.svg');
}
add_action('storefront_before_header', 'add_image_sprite_map');

Use the icon wherever You want

<a target="_blank" href="" rel="noopener noreferrer">
    <svg class="fb-svg"><use xlink:href="#fb-icon" /></svg>
</a>