FPGA: Device and Driver

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This PR adds devices and drivers with features of binding, unbinding and probing. The IpDevice class adds additional features for devices which correspond to an ip on the fpga, such as getting the ip name and baseaddress.

Used by #783.

[n-eiling]

I think this should go into common/lib/kernel. Also there we already have a class Device in pci.hpp. Maybe it makes sense to make a top class Device from which you derive PciDevice and PlatformDevice (instead of IpDevice)?

Doesn't this make some of the functions in common/kernel obsolete? Can we remove something there?
Also please add me to the CODEOWNERS file for the new files you created.

[IgnoreWarnings]

I think this should go into common/lib/kernel. Also there we already have a class Device in pci.hpp. Maybe it makes sense to make a top class Device from which you derive PciDevice and PlatformDevice (instead of IpDevice)?

Doesn't this make some of the functions in common/kernel obsolete? Can we remove something there? Also please add me to the CODEOWNERS file for the new files you created.

Thank you for the tip. It is a good Idea to move it to the Kernel.

Refactor

Naming
The existing Device in "pci.cpp", which is specific for PCI devices, should be renamed to PciDevice.

File Structure
The class should be move to its own "PciDevice" file.

Obsolete Code / Integration
PciDevice can be partially integrated with the new system. Obviously the existing PciDevice wasnt designed with inheritance in mind, which makes it tough to identify common grounds.
The whole code there is questionable: it uses hard coded c_strings as paths, c pointers, fprintf instead of logging, obscure naming... e.g.:

if (tmp[0] && strcmp(tmp, "*")) {
long int x = strtol(tmp, &e, 16);                        
if ((e && *e) || (x < 0 || x > 0x7fffffff)) {...}

I dont think it is worth to port this to the modern style in this PR. Just leave it as is.
@n-eiling Whats your opinion on the suggestions?

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I will add you as author.

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Also the Device class i implemented is a toplevel class. IpDevice is what is used for vfio platform devices ;)

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Waiting for #814

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Lets only comment the headers to avoid duplication.