Fix a few internals tests

The internals tests for chacha, poly1305 and siphash were erroneously
made conditional on if mdc2 was enabled.  Corrected to depend on the
correct algorithms being enabled instead.

Reviewed-by: Matt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/2991)
diff --git a/test/recipes/03-test_internal_chacha.t b/test/recipes/03-test_internal_chacha.t
index 58e21f7..bac1328 100644
--- a/test/recipes/03-test_internal_chacha.t
+++ b/test/recipes/03-test_internal_chacha.t
@@ -16,4 +16,4 @@
 plan skip_all => "This test is unsupported in a shared library build on Windows"
     if $^O eq 'MSWin32' && !disabled("shared");
 
-simple_test("test_internal_chacha", "chacha_internal_test", "mdc2");
+simple_test("test_internal_chacha", "chacha_internal_test", "chacha");
diff --git a/test/recipes/03-test_internal_poly1305.t b/test/recipes/03-test_internal_poly1305.t
index 2f5625d..b5809c1 100644
--- a/test/recipes/03-test_internal_poly1305.t
+++ b/test/recipes/03-test_internal_poly1305.t
@@ -16,4 +16,4 @@
 plan skip_all => "This test is unsupported in a shared library build on Windows"
     if $^O eq 'MSWin32' && !disabled("shared");
 
-simple_test("test_internal_poly1305", "poly1305_internal_test", "mdc2");
+simple_test("test_internal_poly1305", "poly1305_internal_test", "poly1305");
diff --git a/test/recipes/03-test_internal_siphash.t b/test/recipes/03-test_internal_siphash.t
index 1a8a617..1817e4e 100644
--- a/test/recipes/03-test_internal_siphash.t
+++ b/test/recipes/03-test_internal_siphash.t
@@ -16,4 +16,4 @@
 plan skip_all => "This test is unsupported in a shared library build on Windows"
     if $^O eq 'MSWin32' && !disabled("shared");
 
-simple_test("test_internal_siphash", "siphash_internal_test", "mdc2");
+simple_test("test_internal_siphash", "siphash_internal_test", "siphash");