Switch bmarks makefile to rv64gcv

Author: jerryz123

benchmarks/Makefile

@@ -47,7 +47,7 @@ RISCV_GCC_OPTS ?= -DPREALLOCATE=1 -mcmodel=medany -static -std=gnu99 -O2 -ffast-
 RISCV_LINK ?= $(RISCV_GCC) -T $(src_dir)/common/test.ld $(incs)
 RISCV_LINK_OPTS ?= -static -nostdlib -nostartfiles -lm -lgcc -T $(src_dir)/common/test.ld
 RISCV_OBJDUMP ?= $(RISCV_PREFIX)objdump --disassemble-all --disassemble-zeroes --section=.text --section=.text.startup --section=.text.init --section=.data
-RISCV_SIM ?= spike --isa=rv$(XLEN)gc
+RISCV_SIM ?= spike --isa=rv$(XLEN)gcv
 
 incs  += -I$(src_dir)/../env -I$(src_dir)/common $(addprefix -I$(src_dir)/, $(bmarks))
 objs  :=