drm/test: Add test cases for drm_rect_rotate_inv()

Insert a parameterized test for the drm_rect_rotate_inv() to ensure its
correctness and prevent future regressions. The test covers all rotation
modes.

It uses the same test cases from drm_test_rect_rotate().

Signed-off-by: Arthur Grillo <arthurgrillo@riseup.net>
Reviewed-by: Maíra Canal <mcanal@igalia.com>
Signed-off-by: Maíra Canal <mairacanal@riseup.net>
Link: https://patchwork.freedesktop.org/patch/msgid/20230418230146.461129-6-arthurgrillo@riseup.net

drm/tests: Add test cases for drm_rect_rotate()

Insert a parameterized test for the drm_rect_rotate() to ensure
correctness and prevent future regressions.

All possible rotation modes are covered by the test.

Signed-off-by: Arthur Grillo <arthurgrillo@riseup.net>
Reviewed-by: Maíra Canal <mcanal@igalia.com>
Signed-off-by: Maíra Canal <mairacanal@riseup.net>
Link: https://patchwork.freedesktop.org/patch/msgid/20230418230146.461129-5-arthurgrillo@riseup.net

drm/tests: Add test cases for drm_rect_calc_vscale()

Insert parameterized test for the drm_rect_calc_vscale() to ensure
correctness and prevent future regressions. Besides the test for the
usual case, tests the exceptions.

It uses the same struct from drm_rect_calc_hscale().

Signed-off-by: Arthur Grillo <arthurgrillo@riseup.net>
Reviewed-by: Maíra Canal <mcanal@igalia.com>
Signed-off-by: Maíra Canal <mairacanal@riseup.net>
Link: https://patchwork.freedesktop.org/patch/msgid/20230418230146.461129-4-arthurgrillo@riseup.net

drm/tests: Add test cases for drm_rect_calc_hscale()

Insert parameterized test for the drm_rect_calc_hscale() to ensure
correctness and prevent future regressions. Besides the test for the
usual case, tests the exceptions.

Signed-off-by: Arthur Grillo <arthurgrillo@riseup.net>
Reviewed-by: Maíra Canal <mcanal@igalia.com>
Signed-off-by: Maíra Canal <mairacanal@riseup.net>
Link: https://patchwork.freedesktop.org/patch/msgid/20230418230146.461129-3-arthurgrillo@riseup.net

drm/tests: Add test cases for drm_rect_intersect()

Insert parameterized tests for the drm_rect_intersect() to ensure
correctness and prevent future regressions.

Also, create a helper for testing if two drm_rects are equal.

Signed-off-by: Arthur Grillo <arthurgrillo@riseup.net>
Reviewed-by: Maíra Canal <mcanal@igalia.com>
Signed-off-by: Maíra Canal <mairacanal@riseup.net>
Link: https://patchwork.freedesktop.org/patch/msgid/20230418230146.461129-2-arthurgrillo@riseup.net

drm/tests: Change "igt_" prefix to "drm_test_"

With the introduction of KUnit, IGT is no longer the only option to run
the DRM unit tests, as the tests can be run through kunit-tool or on
real hardware with CONFIG_KUNIT.

Therefore, remove the "igt_" prefix from the tests and replace it with
the "drm_test_" prefix, making the tests' names independent from the tool
used.

Signed-off-by: Maíra Canal <mairacanal@riseup.net>
Acked-by: David Gow <davidgow@google.com>
Acked-by: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20220911191756.203118-2-mairacanal@riseup.net

drm: selftest: convert drm_rect selftest to KUnit

Considering the current adoption of the KUnit framework, convert the
DRM rect selftest to the KUnit API.

Co-developed-by: Carlos Veras <carlos.craveiro@usp.br>
Signed-off-by: Carlos Veras <carlos.craveiro@usp.br>
Co-developed-by: Matheus Vieira <matheus.vieira.g@usp.br>
Signed-off-by: Matheus Vieira <matheus.vieira.g@usp.br>
Tested-by: David Gow <davidgow@google.com>
Acked-by: Daniel Latypov <dlatypov@google.com>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Signed-off-by: Maíra Canal <maira.canal@usp.br>
Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220708203052.236290-4-maira.canal@usp.br