ppp: use build system CFLAGS when compiling

Upstream-Status: Pending

Override the hard-coded COPTS make variables with
CFLAGS.  Add COPTS into one Makefile that did not
use it.

Signed-off-by: Joe Slater <jslater@windriver.com>

--- a/pppd/plugins/radius/Makefile.linux
+++ b/pppd/plugins/radius/Makefile.linux
@@ -12,7 +12,7 @@ VERSION = $(shell awk -F '"' '/VERSION/ 
 INSTALL	= install
 
 PLUGIN=radius.so radattr.so radrealms.so
-CFLAGS=-I. -I../.. -I../../../include -O2 -fPIC -DRC_LOG_FACILITY=LOG_DAEMON
+CFLAGS=-I. -I../.. -I../../../include $(COPTS) -fPIC -DRC_LOG_FACILITY=LOG_DAEMON
 
 # Uncomment the next line to include support for Microsoft's
 # MS-CHAP authentication protocol.