MBEDTLS_CTR_DRBG_USE_128_BIT_KEY: add selftest data

In the CTR_DRBG module, add selftest data for when
MBEDTLS_CTR_DRBG_USE_128_BIT_KEY is enabled.

I generated the test data by running our own code. This is ok because
we have other tests that ensure that the algorithm is implemented
correctly.

This makes programs/self/selftest pass when
MBEDTLS_CTR_DRBG_USE_128_BIT_KEY is enabled.
diff --git a/library/ctr_drbg.c b/library/ctr_drbg.c
index 047bb2a..b6fcc02 100644
--- a/library/ctr_drbg.c
+++ b/library/ctr_drbg.c
@@ -712,6 +712,15 @@
     { 0x1b, 0x54, 0xb8, 0xff, 0x06, 0x42, 0xbf, 0xf5,
       0x21, 0xf1, 0x5c, 0x1c, 0x0b, 0x66, 0x5f, 0x3f };
 
+#if defined(MBEDTLS_CTR_DRBG_USE_128_BIT_KEY)
+static const unsigned char result_pr[16] =
+    { 0x95, 0x3c, 0xa5, 0xbd, 0x44, 0x1, 0x34, 0xb7,
+      0x13, 0x58, 0x3e, 0x6a, 0x6c, 0x7e, 0x88, 0x8a };
+
+static const unsigned char result_nopr[16] =
+    { 0x6c, 0x25, 0x27, 0x95, 0xa3, 0x62, 0xd6, 0xdb,
+      0x90, 0xfd, 0x69, 0xb5, 0x42, 0x9, 0x4b, 0x84 };
+#else /* MBEDTLS_CTR_DRBG_USE_128_BIT_KEY */
 static const unsigned char result_pr[16] =
     { 0x34, 0x01, 0x16, 0x56, 0xb4, 0x29, 0x00, 0x8f,
       0x35, 0x63, 0xec, 0xb5, 0xf2, 0x59, 0x07, 0x23 };
@@ -719,6 +728,7 @@
 static const unsigned char result_nopr[16] =
     { 0xa0, 0x54, 0x30, 0x3d, 0x8a, 0x7e, 0xa9, 0x88,
       0x9d, 0x90, 0x3e, 0x07, 0x7c, 0x6f, 0x21, 0x8f };
+#endif /* MBEDTLS_CTR_DRBG_USE_128_BIT_KEY */
 
 static size_t test_offset;
 static int ctr_drbg_self_test_entropy( void *data, unsigned char *buf,