Increase the size of spiffs for ESP8285 on Platformio

Continuing the discussion from Having trouble with board_build.partitions in platformio.ini:

Hi! I’m using LittleFs on an ESP8285 with 1MB of onboard memory and I would like to increase the size of SPIFFS. Now in platformio.ini I have an entry board_build.ldscript = eagle.flash.1m512.ld, but when downloading files from the ‘data’ folder I get an error:
lfs warn:475: No more free space 119
lfs_write error(-28): File system is full
I would like a configuration like eagle.flash.1m768.ld , but this is not in the documentation. How can I increase the size for LittleFS?