lib/crypto: tests: Enable Curve25519 test when CRYPTO_SELFTESTS

Now that the Curve25519 library has been disentangled from CRYPTO,
adding CRYPTO_SELFTESTS as a default value of
CRYPTO_LIB_CURVE25519_KUNIT_TEST no longer causes a recursive kconfig
dependency.  Do this, which makes this option consistent with the other
crypto KUnit test options in the same file.

Link: https://lore.kernel.org/r/20250906213523.84915-12-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@kernel.org>

Author: Eric Biggers

lib/crypto/tests/Kconfig

@@ -13,7 +13,7 @@ config CRYPTO_LIB_BLAKE2S_KUNIT_TEST
 config CRYPTO_LIB_CURVE25519_KUNIT_TEST
 	tristate "KUnit tests for Curve25519" if !KUNIT_ALL_TESTS
 	depends on KUNIT
-	default KUNIT_ALL_TESTS
+	default KUNIT_ALL_TESTS || CRYPTO_SELFTESTS
 	select CRYPTO_LIB_BENCHMARK_VISIBLE
 	select CRYPTO_LIB_CURVE25519
 	help