build: Added targets to run tests
Updated the `Makefile` to provide the following new targets:
```
make test              # Run all tests.
make test-image-only   # Only run image tests.
make test-initrd-only  # Only run initrd tests.
```
@@ -32,3 +32,12 @@ initrd: rootfs initrd-only
initrd-only:
@echo Creating initrd image based on "$(DISTRO_ROOTFS)"
"$(MK_DIR)/initrd-builder/initrd_builder.sh" "$(DISTRO_ROOTFS)"
+
+test:
+ "$(MK_DIR)/tests/test_images.sh" "$(DISTRO)"
+
+test-image-only:
+ "$(MK_DIR)/tests/test_images.sh" --test-images-only "$(DISTRO)"
+
+test-initrd-only:
+ "$(MK_DIR)/tests/test_images.sh" --test-initrds-only "$(DISTRO)"
