fix bootstrap flags for codegen

Author: miselin

src/runtime/codegen/CMakeLists.txt

@@ -1,9 +1,11 @@
 list(APPEND GEN_SRCS "${GEN_DIR}/gen_unistd.hv")
 
+separate_arguments(HAVEN_BOOTSTRAP_COMPILE_FLAGS_LIST NATIVE_COMMAND ${HAVEN_BOOTSTRAP_COMPILE_FLAGS})
+
 add_custom_command(
   OUTPUT "${GEN_DIR}/gen_unistd.hv"
   COMMAND ${CMAKE_COMMAND} -E make_directory ${GEN_DIR}
-  COMMAND $<TARGET_FILE:hdr2haven> "asm/unistd_64.h" --bootstrap -I "/usr/include" -I "/usr/include/x86_64-linux-gnu" -o "${GEN_DIR}/gen_unistd.hv"
+  COMMAND $<TARGET_FILE:hdr2haven> "asm/unistd_64.h" --bootstrap ${HAVEN_BOOTSTRAP_COMPILE_FLAGS_LIST} -o "${GEN_DIR}/gen_unistd.hv"
   DEPENDS hdr2haven
   VERBATIM CODEGEN
 )