ecore: add gnutls to DEPENDS

* we explicitly disable openssl, but gnutls is autodetected
  http://git.shr-project.org/git/?p=buildhistory.git;a=commitdiff;h=7c2972a614cb2811962b95e1f0398cf07aafb7a0



Signed-off-by: Martin Jansa <Martin.Jansa@gmail.com>