net/bredbandskollen: fix build with GCC-based architectures, fix pkg-descr

This port needs USES=compiler:c++11-lang to build on GCC architectures. It also specifies directly CXX with =, replace that with ?=.

Add missing includes (sys/types.h and sys/select.h) that GCC doesn't include by default.

Also fix double https in pkg-descr.

PR: 234216
Approved by: tcberner (mentor), zeising (maintainer timeout)
Differential Revision: https://reviews.freebsd.org/D20442