seabios: fix submodule

Commit "36f96c4b target-i386: Add support to migrate vcpu's TSC rate"
updates roms/seabios, appearently by mistake.  Revert this.
Signed-off-by: NGerd Hoffmann <kraxel@redhat.com>
Message-id: 1453460391-7664-1-git-send-email-kraxel@redhat.com
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

seabios @ 01a84bea

-Subproject commit 33fbe13a3e2a01e0ba1087a8feed801a0451db21
+Subproject commit 01a84bea2d28a19d2405c1ecac4bdef17683cc0c