py: libcamera: Move function declarations to common header

The init_py_*() functions are called by the top-level entry point of the
libcamera Python module to initialize different parts of the bindings.
They are declared in py_main.cpp where they are called, and defined in
separate compilation units. This results in functions being defined
without a corresponding declaration, and will generate warnings when we
enable -Wmissing-declarations.

Fix this by moving the function declarations from py_main.c to
py_main.h, and including py_main.h in the various compilation units that
need it.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
9 files changed