MT#55283 enable -Werror=return-type

Turn missing return values into hard errors.

Change-Id: I2f7e5bf11cfdce25fb6432a66b352d6e8103c037

daemon/Makefile

@@ -4,7 +4,7 @@ with_iptables_option ?= yes
 with_transcoding ?= yes
 
 
-CFLAGS?=	-g -Wall -Wextra -Wno-sign-compare -Wno-unused-parameter -Wstrict-prototypes
+CFLAGS?=	-g -Wall -Wextra -Wno-sign-compare -Wno-unused-parameter -Wstrict-prototypes -Werror=return-type
 CFLAGS+=	-pthread -fno-strict-aliasing
 CFLAGS+=	-std=c99
 CFLAGS+=	$(shell pkg-config --cflags glib-2.0)

recording-daemon/Makefile

@@ -1,6 +1,6 @@
 TARGET=		rtpengine-recording
 
-CFLAGS?=	-g -Wall -Wextra -Wno-sign-compare -Wno-unused-parameter -Wstrict-prototypes
+CFLAGS?=	-g -Wall -Wextra -Wno-sign-compare -Wno-unused-parameter -Wstrict-prototypes -Werror=return-type
 CFLAGS+=	-pthread -I. -I../lib/ -I../kernel-module/
 CFLAGS+=	-std=c99 -fno-strict-aliasing
 CFLAGS+=	-D_GNU_SOURCE -D_POSIX_SOURCE -D_POSIX_C_SOURCE

t/Makefile

@@ -2,7 +2,7 @@ TARGET=		all-tests
 
 with_transcoding ?= yes
 
-CFLAGS?=	-g -Wall -Wextra -Wno-sign-compare -Wno-unused-parameter -Wstrict-prototypes
+CFLAGS?=	-g -Wall -Wextra -Wno-sign-compare -Wno-unused-parameter -Wstrict-prototypes -Werror=return-type
 PRELOAD_CFLAGS := $(CFLAGS)
 CFLAGS+=	-pthread -fno-strict-aliasing
 CFLAGS+=	-std=c99