/usr/include/at-spi-2.0/atspi/ is in libatspi2.0-dev 2.14.0-1.
This file is owned by root:root, with mode 0o755.
..
/usr/include/at-spi-2.0/atspi/atspi-accessible.h
/usr/include/at-spi-2.0/atspi/atspi-action.h
/usr/include/at-spi-2.0/atspi/atspi-application.h
/usr/include/at-spi-2.0/atspi/atspi-collection.h
/usr/include/at-spi-2.0/atspi/atspi-component.h
/usr/include/at-spi-2.0/atspi/atspi-constants.h
/usr/include/at-spi-2.0/atspi/atspi-device-listener-private.h
/usr/include/at-spi-2.0/atspi/atspi-device-listener.h
/usr/include/at-spi-2.0/atspi/atspi-document.h
/usr/include/at-spi-2.0/atspi/atspi-editabletext.h
/usr/include/at-spi-2.0/atspi/atspi-enum-types.h
/usr/include/at-spi-2.0/atspi/atspi-event-listener-private.h
/usr/include/at-spi-2.0/atspi/atspi-event-listener.h
/usr/include/at-spi-2.0/atspi/atspi-gmain.c
/usr/include/at-spi-2.0/atspi/atspi-gmain.h
/usr/include/at-spi-2.0/atspi/atspi-hyperlink.h
/usr/include/at-spi-2.0/atspi/atspi-hypertext.h
/usr/include/at-spi-2.0/atspi/atspi-image.h
/usr/include/at-spi-2.0/atspi/atspi-matchrule.h
/usr/include/at-spi-2.0/atspi/atspi-misc.h
/usr/include/at-spi-2.0/atspi/atspi-object.h
/usr/include/at-spi-2.0/atspi/atspi-private.h
/usr/include/at-spi-2.0/atspi/atspi-registry.h
/usr/include/at-spi-2.0/atspi/atspi-relation.h
/usr/include/at-spi-2.0/atspi/atspi-selection.h
/usr/include/at-spi-2.0/atspi/atspi-stateset.h
/usr/include/at-spi-2.0/atspi/atspi-table-cell.h
/usr/include/at-spi-2.0/atspi/atspi-table.h
/usr/include/at-spi-2.0/atspi/atspi-text.h
/usr/include/at-spi-2.0/atspi/atspi-types.h
/usr/include/at-spi-2.0/atspi/atspi-value.h
/usr/include/at-spi-2.0/atspi/atspi.h