[perl #39043] [TODO] Dynamic PMCs should not include 'parrot/parrot.h'

[Bernhard Schmalhofer]

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In 'include/parrot/parrot.h' it quite sensibly says:

/* Only parrot core files should include this file.
Extensions should include <parrot/extend.h>.
Programs embedding parrot should include <parrot/embed.h>.
*/

However all dynamic PMCs in src/dynpmc and most, if not all, language
PMCs are
also including 'parrot/parrot.h'.

So the dependencies on symbols not defined in 'extend.h' should go away.