Fix double definition of DOXYGEN in makefiles
Fix double definition of DOXYGEN in makefiles

UBERTC/osl,UBERTC/osl,realincubus/openscop,ftynse/openscop,realincubus/openscop,realincubus/openscop,Haerezis/openscop,BobSaget-Mod/osl-saber,periscop/openscop,BobSaget-Mod/osl-saber,BobSaget-Mod/osl-saber,Haerezis/openscop,periscop/openscop,UBERTC/osl,periscop/openscop,ftynse/openscop,ftynse/openscop,Haerezis/openscop