How to fix Ubuntu 16 update errors?

Question

linux

I can not update Ubuntu 16.
When updating, it says that there is not enough space on /boot.
And when I try to manually remove the old kernels, as they suggest here - https://gist.github.com/ipbastola/2760cfc28be62a5e...

does not work. I get:

sudo apt-get purge linux-image-4.4.0-170-generic
Reading package lists... Done
Building dependency tree
Reading state information... Done
You might want to run 'apt-get -f install' to correct these:
The following packages have unmet dependencies:
 linux-image-generic : Depends: linux-image-4.4.0-210-generic but it is not going to be installed or
                                linux-image-unsigned-4.4.0-210-generic but it is not going to be installed
                       Recommends: thermald but it is not going to be installed
 linux-modules-extra-4.4.0-170-generic : Depends: linux-image-4.4.0-170-generic but it is not going to be installed or
                                                  linux-image-unsigned-4.4.0-170-generic but it is not going to be installed
 linux-modules-extra-4.4.0-184-generic : Depends: linux-image-4.4.0-184-generic but it is not going to be installed or
                                                  linux-image-unsigned-4.4.0-184-generic but it is not going to be installed
 linux-modules-extra-4.4.0-210-generic : Depends: linux-image-4.4.0-210-generic but it is not going to be installed or
                                                  linux-image-unsigned-4.4.0-210-generic but it is not going to be installed
E: Unmet dependencies. Try 'apt-get -f install' with no packages (or specify a solution).

How to be? Thanks in advance!