Add configurations for SunOS CoreCLR managed build

[am11]

• Add msbuild configurations for coreclr managed build.
• Add SunOS and NetBSD where it was missing.
• Set IMAGE_FILE_MACHINE_NATIVE_OS_OVERRIDE to 1992 for SunOS (initial release year of Solaris).
• Align maxProcesses/NumProc handling in shell scripts.
• Fix some cmake configurations for cross compile (target vs. host).

Contributes to: #34944.

[ghost]

Tagging subscribers to this area: @ViktorHofer
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[am11]

cc @janvorli, @jkotas

[janvorli]

@ViktorHofer I have noticed that the TestNugetRuntimeId is set to ubuntu 14.04. Do we really use packages for that out-of -life version of Ubuntu or is this property actually never used?

[janvorli]

I wonder if we should update the

runtime/src/libraries/System.Runtime.InteropServices.RuntimeInformation/src/System/Runtime/InteropServices/RuntimeInformation/OSPlatform.cs

Lines 11 to 19 in 3b4c5a5

	public static OSPlatform Browser { get; } = new OSPlatform("BROWSER");
	public static OSPlatform FreeBSD { get; } = new OSPlatform("FREEBSD");
	public static OSPlatform Linux { get; } = new OSPlatform("LINUX");
	public static OSPlatform OSX { get; } = new OSPlatform("OSX");
	public static OSPlatform Windows { get; } = new OSPlatform("WINDOWS");

Otherwise LGTM

[am11]

I wonder if we should update the runtime/src/libraries/System.Runtime.InteropServices.RuntimeInformation/src/System/Runtime/InteropServices/RuntimeInformation/OSPlatform.cs

I haven't touched :/src/libraries and :/src/installer managed components as part of this PR, that is the next step.

[janvorli]

I haven't touched :/src/libraries and :/src/installer managed components as part of this PR, that is the next step.

Ok, makes sense, I wasn't sure about the extent of this change.

[krytarowski]

Thanks for the NetBSD bits.