x86/call32: reserve space for saving 64-bit sp on 32-bit stack
x86/call32: reserve space for saving 64-bit sp on 32-bit stack

I prefer this to be done in callee, than in caller for simplicity.

Cc: Cyrill Gorcunov <7a1ea01eee6961eb1e372e3508c2670446d086f4@openvz.org>
Signed-off-by: Dmitry Safonov <5aea3f9692c8a01793193334616ae8fad2bc748a@virtuozzo.com>
Signed-off-by: Pavel Emelyanov <c9a32589e048e044184536f7ac71ef92fe82df3e@virtuozzo.com>

KKoukiou/criu-remote,KKoukiou/criu-remote,KKoukiou/criu-remote,KKoukiou/criu-remote,KKoukiou/criu-remote,KKoukiou/criu-remote