Bug#738735: linop: FTBFS: dh_sphinxdoc: Sphinx documentation not found

[Aaron M. Ucko]

Source: linop
Version: 0.8-1
Severity: serious
Justification: fails to build from source

Builds of linop covering only its architecture-dependent binary
packages and skipping its architecture-independent -doc package (as on
the autobuilders) have been faiing:

     dh_sphinxdoc -a -O--buildsystem=pybuild
  dh_sphinxdoc: Sphinx documentation not found
  make: *** [binary-arch] Error 2

Please arrange to invoke dh --with sphinxdoc only when it would have
something to do.

Thanks!