Fix typo in #ifdef
Since length is checked afterwards anyway, no security risk here
diff --git a/include/polarssl/ssl.h b/include/polarssl/ssl.h
index a4cd70e..f4f8f01 100644
--- a/include/polarssl/ssl.h
+++ b/include/polarssl/ssl.h
@@ -444,7 +444,7 @@
#if defined(POLARSSL_KEY_EXCHANGE_RSA_PSK_ENABLED)
unsigned char _pms_rsa_psk[52 + POLARSSL_PSK_MAX_LEN]; /* RFC 4279 4 */
#endif
-#if defined(POLARSSL_KEY_EXCHANGE_DHE_PSK_ENABLED)
+#if defined(POLARSSL_KEY_EXCHANGE_ECDHE_PSK_ENABLED)
unsigned char _pms_ecdhe_psk[4 + POLARSSL_ECP_MAX_BYTES
+ POLARSSL_PSK_MAX_LEN]; /* RFC 5489 2 */
#endif