Add no-ec build

Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/2626)

.travis.yml

diff --git a/.travis.yml b/.travis.yml
index a60c402..7b9e671 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -34,6 +34,7 @@
     - CONFIG_OPTS="no-pic --strict-warnings" BUILDONLY="yes" CHECKDOCS="yes"
     - CONFIG_OPTS="no-engine no-shared --strict-warnings" BUILDONLY="yes"
     - CONFIG_OPTS="no-stdio --strict-warnings" BUILDONLY="yes"
+    - CONFIG_OPTS="no-ec" BUILDONLY="yes"
 
 matrix:
     include: