Fix interlck.c to work on Mac OS again...
Fix interlck.c to work on Mac OS again...

mmeeks, we love your patch; however, some of us are forced to use the very
old 4.0 version of GCC (I blame Apple) and __sync_add_and_fetch() wasn't
added until version 4.4.

PS: Moving the target OS version to 10.5 wont help because that still uses
the 4.2.1 version.

JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core