build: Use AM_CFLAGS instead of GCC_CFLAGS

AM_CFLAGS is the default for any target that doesn't specify its
own cflags.  We should use AM_CFLAGS in preference to GCC_CFLAGS
so we can change AM_CFLAGS and get all targets.

Signed-off-by: Derek Foreman <derekf@osg.samsung.com>
Reviewed-by: Jon A. Cruz <jonc@osg.samsung.com>
[pekka: fixed patch conflicts]
Signed-off-by: Pekka Paalanen <pekka.paalanen@collabora.co.uk>
1 file changed