False positive WARNING from kernel-doc-man builder

[return42]

The kenerl-doc-man builder produces false positive warnings when using the :internal: option of the kernel-doc directive:

docs/linuxdoc-howto/test_internals.c:24: WARNING: Duplicate explicit target name: "test_internals_a.bar".
docs/linuxdoc-howto/test_internals.c:24: WARNING: Duplicate C declaration, also defined at linuxdoc-howto/kernel-doc-tests:24.
Declaration is '.. c:function:: int bar(int a,  ...)'.
docs/linuxdoc-howto/test_internals.c:27: WARNING: Duplicate explicit target name: "test_internals_a.bar.description".
docs/linuxdoc-howto/test_internals.c:30: WARNING: Duplicate explicit target name: "test_internals_a.bar.example".
docs/linuxdoc-howto/test_internals.c:33: WARNING: Duplicate explicit target name: "test_internals_a.bar.return".
docs/linuxdoc-howto/test_internals.c:43: WARNING: Duplicate explicit target name: "test_internals_a.internal_function".
docs/linuxdoc-howto/test_internals.c:43: WARNING: Duplicate C declaration, also defined at linuxdoc-howto/kernel-doc-tests:43.
Declaration is '.. c:function:: int internal_function( void)'.
docs/linuxdoc-howto/test_internals.c:45: WARNING: Duplicate explicit target name: "test_internals_a.internal_function.context".
docs/linuxdoc-howto/test_internals.c:47: WARNING: Duplicate explicit target name: "test_internals_a.internal_function.return".
docs/linuxdoc-howto/test_internals.c:4: WARNING: Duplicate explicit target name: "test_internals_b.foo".
docs/linuxdoc-howto/test_internals.c:4: WARNING: Duplicate C declaration, also defined at linuxdoc-howto/kernel-doc-tests:4.
Declaration is '.. c:function:: int foo(int a,  ...)'.
docs/linuxdoc-howto/test_internals.c:7: WARNING: Duplicate explicit target name: "test_internals_b.foo.description".
docs/linuxdoc-howto/test_internals.c:10: WARNING: Duplicate explicit target name: "test_internals_b.foo.example".
docs/linuxdoc-howto/test_internals.c:13: WARNING: Duplicate explicit target name: "test_internals_b.foo.return".
docs/linuxdoc-howto/test_internals.c:43: WARNING: Duplicate explicit target name: "test_internals_b.internal_function".
docs/linuxdoc-howto/test_internals.c:43: WARNING: Duplicate C declaration, also defined at linuxdoc-howto/kernel-doc-tests:43.
Declaration is '.. c:function:: int internal_function( void)'.
docs/linuxdoc-howto/test_internals.c:45: WARNING: Duplicate explicit target name: "test_internals_b.internal_function.context".
docs/linuxdoc-howto/test_internals.c:47: WARNING: Duplicate explicit target name: "test_internals_b.internal_function.return".
docs/linuxdoc-howto/kernel-doc-tests.rst:355: WARNING: using option :export: but there are no exported symbols