Bug 10987: (follow-up) fix display of authorities containing only one see from or...

Bug 10987: (follow-up) fix display of authorities containing only one see from or see also lnik

This patch fixes an incorrect test on the number of see from and
see also links in the authority record, as otherwise if a record
had only one 4XX or 5XX, the linked headings weren't displayed at
all.  This patch also makes the test consistent across the staff
theme and the two OPAC themes.

Signed-off-by: Galen Charlton <gmc@esilibrary.com>
(cherry picked from commit e686dd25438b66de751551c8f8fecff115b661d4)
Signed-off-by: Fridolin Somers <fridolin.somers@biblibre.com>