Remove +warn_export_all from the enabled warnings by default

People who don't want export_all simply don't use it. The
warning is annoying for those edge cases where it's actually
useful, as it can't be disabled on a per-file basis.

core/erlc.mk

@@ -5,8 +5,8 @@
 
 # Configuration.
 
-ERLC_OPTS ?= -Werror +debug_info +warn_export_all +warn_export_vars \
-	+warn_shadow_vars +warn_obsolete_guard # +bin_opt_info +warn_missing_spec
+ERLC_OPTS ?= -Werror +debug_info +warn_export_vars +warn_shadow_vars \
+	+warn_obsolete_guard # +bin_opt_info +warn_export_all +warn_missing_spec
 COMPILE_FIRST ?=
 COMPILE_FIRST_PATHS = $(addprefix src/,$(addsuffix .erl,$(COMPILE_FIRST)))
 ERLC_EXCLUDE ?=

erlang.mk

@@ -206,8 +206,8 @@ help::
 
 # Configuration.
 
-ERLC_OPTS ?= -Werror +debug_info +warn_export_all +warn_export_vars \
-	+warn_shadow_vars +warn_obsolete_guard # +bin_opt_info +warn_missing_spec
+ERLC_OPTS ?= -Werror +debug_info +warn_export_vars +warn_shadow_vars \
+	+warn_obsolete_guard # +bin_opt_info +warn_export_all +warn_missing_spec
 COMPILE_FIRST ?=
 COMPILE_FIRST_PATHS = $(addprefix src/,$(addsuffix .erl,$(COMPILE_FIRST)))
 ERLC_EXCLUDE ?=