Coverity 1093664: Out-of-bounds write

git-svn-id: svn://svn.icculus.org/fs2open/trunk/fs2_open@9978 387891d4-d844-0410-90c0-e4c51a9137d3
Coverity fixes from Flaming_Sword

Uninitialized scalar field 1093859 1093917 1093810
Out-of-bounds read/access 1093669 1093670
Logically dead code 1093413 1093396 1093407 1093408 1093409 1093410 1093423 1093427 1093390
Allocation size mismatch 1093729 1093728
Unused pointer value 1093921 1093922
Wrong sizeof argument 1093732 1093731
Operands don't affect result 1093365
Dereference after null check/return value 1093475 1093455 1093627

git-svn-id: svn://svn.icculus.org/fs2open/trunk/fs2_open@9979 387891d4-d844-0410-90c0-e4c51a9137d3