build_all_configs.sh: Use CPPFLAGS instead of CFLAGS (#41)
build_all_configs.sh: Use CPPFLAGS instead of CFLAGS (#41)

`SPIFFS_OBJ_META_LEN` was not properly set for all languages (only for c).
See output of `mkspiffs --version`.
igrr/mkspiffs,igrr/mkspiffs,igrr/mkspiffs