Merge pull request #2529 from Pinata-Consulting/synth-testing-creature-comfort

synthesis: creature comfort for testing SYNTH_HIERARCHICAL=1/0 on command line

Author: maliberty

flow/designs/asap7/riscv32i/config.mk

@@ -2,7 +2,7 @@ export DESIGN_NICKNAME ?= riscv32i
 export DESIGN_NAME = riscv_top
 export PLATFORM    = asap7
 
-export SYNTH_HIERARCHICAL = 1
+export SYNTH_HIERARCHICAL ?= 1
 
 export RTLMP_MIN_INST = 1000
 export RTLMP_MAX_INST = 3500