Prevent original "-O" flag from being overridden
Prevent original "-O" flag from being overridden

If multiple packages specify a gcc optimization level ("-O<n>"), discard
all but the first.  This prevents the build profile "-O" setting from
overriding those specified in package-specific cflags.

apache/incubator-mynewt-newt,apache/incubator-mynewt-newt