In a manner similar to one of commit 9303ed3 ("Makefiles: move
-Wa,--noexecstack out of CFLAGS"), let's move this option to
linker flags (see the abovementioned commit for reasoning).

travis-ci: success for series starting with [1/3] compel: mv noexecstack from CFLAGS to LDFLAGS
Signed-off-by: Kir Kolyshkin <kir@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>
Signed-off-by: Andrei Vagin <avagin@virtuozzo.com>