Added location to ConditionalDeclaration and StaticIfDeclaration

[AsterMiha]

Continuing adding location to the remaining AST nodes

Since I chose to let the location of DVCondition start from the actual condition instead of the version and debug symbols[1], I set the location of ConditionalDeclaration to these symbols, as this is the node used for both VersionCondition and DebugCondition.

StaticIfCondition already starts at static so, at the moment, StaticIfDeclaration would have the exact same location. Should the location of StaticIfCondition be changed to only point to the condition?

[1] #11907

[dlang-bot]

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Testing this PR locally

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dub run digger -- build "master + dmd#11914"

[thewilsonator]

Rebase to fix build kite. Circle I have no idea.

[12345swordy]

All green here.