Fixup debug.h and ssl_internal.h: Add missing include of ecdh.h

Previously, this wasn't necessary because ecdh.h was included
through ssl.h, but now that this is no longer the case (because
ssl.h doesn't use ECDH), we have to include it explicitly.

include/mbedtls/debug.h

@@ -36,6 +36,10 @@
 #include "ecp.h"
 #endif
 
+#if defined(MBEDTLS_ECDH_C)
+#include "ecdh.h"
+#endif
+
 #if defined(MBEDTLS_DEBUG_C)
 
 #define MBEDTLS_DEBUG_STRIP_PARENS( ... )   __VA_ARGS__

include/mbedtls/ssl_internal.h

@@ -54,6 +54,14 @@
 #include "ecjpake.h"
 #endif
 
+#if defined(MBEDTLS_ECP_C)
+#include "ecp.h"
+#endif
+
+#if defined(MBEDTLS_ECDH_C)
+#include "ecdh.h"
+#endif
+
 #if defined(MBEDTLS_USE_TINYCRYPT)
 #include "tinycrypt/ecc.h"
 #include "tinycrypt/ecc_dh.h"