Yes it is.
I just done it - and it works!! 
You have to edit the lora_gateway/libloragw/inc/imst_rpi.h file and change the default #define SPI_SPEED 8000000 to #define SPI_SPEED 500000
I then rebuilt the code on resin.io and pushed it to both my gateways and now they start first time - even after a re-boot!
Job done!