gbuild: add missing dependency on regmerge
gbuild: add missing dependency on regmerge

visible with 'make udkapi.all'

Change-Id: I7fcd72e4d6849e3457551d85d507a15f6f72077b

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