remove an old SDC define (#3352)

this is no longer used by Microphysics

Author: zingale

Exec/Make.Castro

@@ -210,10 +210,6 @@ ifeq ($(USE_REACT), TRUE)
   DEFINES += -DREACTIONS
 endif
 
-ifeq ($(USE_SIMPLIFIED_SDC), TRUE)
-  DEFINES += -DSDC_EVOLVE_ENERGY
-endif
-
 ifeq ($(USE_TRUE_SDC), TRUE)
   Bdirs += Source/sdc
 endif