fixed: addoninstaller unguarded null pointer after b0825b1a212849e52fca27409ea87e81591f7cf4
Merge pull request #2489 from Voyager1/fix_addoninstaller_np

fixed: addoninstaller unguarded null pointer after #2475
Only add to preDeps when it's not in there.
depends: fix sed in libgcrypt which wants to change the optimisation but also might change other stuff we don't want (e.x. XBMC-OSX to XBMC-O1SX :p)