libcanfestival: Don't force -fhonour-opts

-fhonour-copts is an OpenWrt/LEDE toolchain specific patch, forcing it
will make external toolchain fail to build this package. What we need
instead is a way to override CFLAGS from the different Makefile files so
rename the patch to illustrate that.

Fixes: 317c2469d9 ("libcanfestival: fix several small build process issues")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>

libs/libcanfestival/Makefile

@@ -8,7 +8,7 @@
 include $(TOPDIR)/rules.mk
 
 PKG_NAME:=libcanfestival
-PKG_RELEASE:=5
+PKG_RELEASE:=6
 
 PKG_SOURCE_VERSION:=8bfe0ac00cdb
 PKG_SOURCE_URL:=http://dev.automforge.net/CanFestival-3/archive/$(PKG_SOURCE_VERSION).tar.bz2?_dummyfilename=

libs/libcanfestival/patches/004-override-cflags.patch

@@ -5,7 +5,7 @@
  CC = SUB_CC
  OPT_CFLAGS = -O2
 -CFLAGS = SUB_OPT_CFLAGS
-+CFLAGS = SUB_OPT_CFLAGS -fhonour-copts
++CFLAGS ?= SUB_OPT_CFLAGS
  PROG_CFLAGS = SUB_PROG_CFLAGS
  PREFIX = SUB_PREFIX
  TARGET = SUB_TARGET
@@ -16,7 +16,7 @@
  
  else
 -CFLAGS = SUB_OPT_CFLAGS
-+CFLAGS = SUB_OPT_CFLAGS -fhonour-copts
++CFLAGS ?= SUB_OPT_CFLAGS
  
  ifeq ($(TARGET),none)
  canfestival: libcanfestival.o
@@ -27,7 +27,7 @@
  
  else
 -CFLAGS = SUB_OPT_CFLAGS
-+CFLAGS = SUB_OPT_CFLAGS -fhonour-copts
++CFLAGS ?= SUB_OPT_CFLAGS
  
  driver: libcanfestival_$(TARGET).a
  
@@ -38,7 +38,7 @@
  CC = SUB_CC
  OPT_CFLAGS = -O2
 -CFLAGS = SUB_OPT_CFLAGS
-+CFLAGS = SUB_OPT_CFLAGS -fhonour-copts
++CFLAGS ?= SUB_OPT_CFLAGS
  PROG_CFLAGS = SUB_PROG_CFLAGS
  OS_NAME = SUB_OS_NAME
  ARCH_NAME = SUB_ARCH_NAME