doc: do not put version in breadcrumbs for daily docs

# Add any paths that contain custom themes here, relative to this directory.

html_theme_path = ['./themes']

if tags.has('release'):

    docs_title = 'Docs / %s' %(version)

else:

    docs_title = 'Docs'

# The name for this set of Sphinx documents.  If None, it defaults to

# "<project> v<release> documentation".

html_title = "Zephyr Project Documentation"

# docs_title is used in the breadcrumb title in the zephyr docs theme

html_context = {

    'show_license': html_show_license,

    'docs_title': 'Docs / ' + version,

    'docs_title': docs_title,

}