net/oic: Fail init if any interface fails
net/oic: Fail init if any interface fails

oc_connectivity_init() would succeed if at least one interface was
successfully initialized.  This allowed interfaces to silently fail.

This commit changes oc_connectivity_init() so that it fails unless *all*
interfaces successfully initialize.

mlaz/mynewt-core,mlaz/mynewt-core,mlaz/mynewt-core,mlaz/mynewt-core,mlaz/mynewt-core