Added -Wno-error=comment to CXXFLAGS

This prevents gcc from throwing an error when including MLIR
header files.

Makefile.sub

@@ -34,7 +34,7 @@ MLIR_ROOT = $(JLM_ROOT)/lib/mlir-rvsdg/
 
 # -gdwarf-4 is used since the valgrind version in Ubuntu 22.04 doesn't support dwarf-5, 
 #  which is produced by default by clang-14
-CXXFLAGS += --std=c++17 -Wall -Wpedantic -Wextra -Wno-unused-parameter -Werror -Wfatal-errors -gdwarf-4 -I$(MLIR_ROOT)/include -I$(MLIR_ROOT)/include
+CXXFLAGS += --std=c++17 -Wall -Wpedantic -Wno-error=comment -Wextra -Wno-unused-parameter -Werror -Wfatal-errors -gdwarf-4 -I$(MLIR_ROOT)/include -I$(MLIR_ROOT)/include
 CXXFLAGS_DEBUG += -g -DJLM_DEBUG -DJLM_ENABLE_ASSERTS
 
 $(JLM_BUILD)/%.la: $(JLM_ROOT)/%.cpp