update pppd patch and build shell script, fix buildroot glibc build bug

guowenxue

2019-08-11 44b6985a5c9724e5f8b8f30000c5f022dee42863

 3rdparty/dhcpd/build.sh

@@ -84,8 +84,8 @@
    check_result "ERROR: compile ${SRC_NAME} failure"

    ${STRIP} server/${IMG_NAME}
    cp server/${IMG_NAME} ${PREFIX_PATH} ../
    cp client/dhclient  ${PREFIX_PATH} ../
    cp server/${IMG_NAME} ${PREFIX_PATH} 
    cp client/dhclient  ${PREFIX_PATH} 

    cd -
}