Bug 21585: Ignore missing firstname in ILL requests table

Bug 21585: Ignore missing firstname in ILL requests table

To test:
- Make sure you have a patron with just a surname and no firstname
- Create an ILL request so that the name of this patron shows up in
  the Patron column of the ILL requests table
- Before the patch, the name will display as "null Surname"
- Apply the patch
- Reload the ILL requests page
- The name should now display as just "Surname"
- Sign ye merrily off

Signed-off-by: Andrew Isherwood <andrew.isherwood@ptfs-europe.com>
Signed-off-by: Josef Moravec <josef.moravec@gmail.com>
Signed-off-by: Nick Clemens <nick@bywatersolutions.com>
(cherry picked from commit 5ea877f6cba299373e0ebb9c59f8797baba98bec)
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>
(cherry picked from commit da971a81da893ca625d78b172ccab8f4131a8664)
Signed-off-by: Fridolin Somers <fridolin.somers@biblibre.com>