tests: roll out igt_simple_init/igt_simple_main

Also use igt_skip a bit more to simplify some of the tests.

Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

tests/gem_unfence_active_buffers.c

@@ -63,7 +63,7 @@ uint32_t devid;
 
 uint32_t data[TEST_SIZE/4];
 
-int main(int argc, char **argv)
+igt_simple_main
 {
 	int i, ret, fd, num_fences;
 	drm_intel_bo *busy_bo, *test_bo;
@@ -164,6 +164,4 @@ int main(int argc, char **argv)
 		}
 	}
 	intel_batchbuffer_flush(batch);
-
-	return 0;
 }