Support compilation on additional host sytstems

[degory]

Enhancements:

• Support compilation on additional host systems (requires explicit ILAsm package reference, closes No ilasm for Raspberry PI - Exec format error #917)

[degory]

@quanglewangle I'm going to merge this PR - with these changes I'm able to build and run ghul projects on my PI on Ubuntu Server 20.04 64-bit. Feel free to re-open #917 if it doesn't work for you. Note you will need to add an appropriate IL assembler package reference for your ARM host, e.g:

<PackageReference Include="runtime.linux-arm.Microsoft.NETCore.ILAsm" Version="6.0.0" GeneratePathProperty="true" />

or

<PackageReference Include="runtime.linux-arm64.Microsoft.NETCore.ILAsm" Version="6.0.0" GeneratePathProperty="true" />

(Which you need depends on whether you're using a 32-bit or 64-bit distro. GeneratePathProperty="true" is needed so the compile target can find the IL assembler package files)