Fix the matchbox-panel seg fault on netbook & emenlow
netbook & emenlow use "-march=core2"(in tune-atom.inc) instead of "=i586"(for
qemux86), plus the "-fomit-frame-pointer" in default FULL_OPTIMIZATION, this
cause strange seg fault when starting matchbox-panel.
seg fault happened @ tmp_reset_bg (gtk+-2.20.1/gdk/x11/gdkwindow-x11.c), which
is inline function extended inside _gdk_x11_window_tmp_unset_bg. When expanding
GDK_DRAWABLE_XID(obj->bg_pixmap) with gcc 4.5.0 optimization, a function call
is missing. Saving a local var to stack also disappeared, but still tried to
restore it from stack, which cause seg fault after getting a worng value.
This fix avoid "-fomit-frame-pointer" in gtk+ on netbook & emenlow.
