Remove obsolete options from config.py

These options haven't existed for a long time.
diff --git a/scripts/config.py b/scripts/config.py
index 54c2937..9e76483 100755
--- a/scripts/config.py
+++ b/scripts/config.py
@@ -169,9 +169,6 @@
             'MBEDTLS_HAVE_SSE2',
             'MBEDTLS_PLATFORM_NO_STD_FUNCTIONS',
             'MBEDTLS_CTR_DRBG_USE_128_BIT_KEY',
-            'MBEDTLS_ECP_DP_M221_ENABLED',
-            'MBEDTLS_ECP_DP_M383_ENABLED',
-            'MBEDTLS_ECP_DP_M511_ENABLED',
             'MBEDTLS_NO_DEFAULT_ENTROPY_SOURCES',
             'MBEDTLS_NO_PLATFORM_ENTROPY',
             'MBEDTLS_RSA_NO_CRT',