plugins/c_src.mk: update CFLAGS/CXXFLAGS/LDFLAGS for OS X

* Add the following flags to LDFLAGS needed at linkage for OS X,
  and remove the following flags from CFLAGS and CPPFLAGS:
  `-arch x86_64 -flat_namespace -undefined suppress`

erlang.mk

@@ -592,8 +592,9 @@ C_SRC_OUTPUT ?= $(CURDIR)/priv/$(PROJECT).so
 UNAME_SYS := $(shell uname -s)
 ifeq ($(UNAME_SYS), Darwin)
 	CC ?= cc
-	CFLAGS ?= -O3 -std=c99 -arch x86_64 -flat_namespace -undefined suppress -finline-functions -Wall -Wmissing-prototypes
-	CXXFLAGS ?= -O3 -arch x86_64 -flat_namespace -undefined suppress -finline-functions -Wall
+	CFLAGS ?= -O3 -std=c99 -arch x86_64 -finline-functions -Wall -Wmissing-prototypes
+	CXXFLAGS ?= -O3 -arch x86_64 -finline-functions -Wall
+	LDFLAGS ?= -arch x86_64 -flat_namespace -undefined suppress
 else ifeq ($(UNAME_SYS), FreeBSD)
 	CC ?= cc
 	CFLAGS ?= -O3 -std=c99 -finline-functions -Wall -Wmissing-prototypes

plugins/c_src.mk

@@ -15,8 +15,9 @@ C_SRC_OUTPUT ?= $(CURDIR)/priv/$(PROJECT).so
 UNAME_SYS := $(shell uname -s)
 ifeq ($(UNAME_SYS), Darwin)
 	CC ?= cc
-	CFLAGS ?= -O3 -std=c99 -arch x86_64 -flat_namespace -undefined suppress -finline-functions -Wall -Wmissing-prototypes
-	CXXFLAGS ?= -O3 -arch x86_64 -flat_namespace -undefined suppress -finline-functions -Wall
+	CFLAGS ?= -O3 -std=c99 -arch x86_64 -finline-functions -Wall -Wmissing-prototypes
+	CXXFLAGS ?= -O3 -arch x86_64 -finline-functions -Wall
+	LDFLAGS ?= -arch x86_64 -flat_namespace -undefined suppress
 else ifeq ($(UNAME_SYS), FreeBSD)
 	CC ?= cc
 	CFLAGS ?= -O3 -std=c99 -finline-functions -Wall -Wmissing-prototypes