You’re missing the amdgpu firmware:
[ 3.778567] amdgpu 0000:05:00.0: Direct firmware load for amdgpu/renoir_gpu_info.bin failed with error -2
[ 3.778570] amdgpu 0000:05:00.0: Failed to load gpu_info firmware "amdgpu/renoir_gpu_info.bin"
[ 3.778576] amdgpu 0000:05:00.0: Fatal error during GPU init
Like mentioned in the other thread I linked to, it is not advisable to do this on 18.04. Besides having a compiler mismatch, you’ll have to copy over the missing renoir firmware files from amdgpu - kernel/git/firmware/linux-firmware.git - Repository of firmware blobs for use with the Linux kernel
to /lib/firmware/amdgpu.