Correct definitions for FD_CMD_SAVE and FD_CMD_RESTORE

Correct definitions for FD_CMD_SAVE and FD_CMD_RESTORE

Correct definitions for FD_CMD_SAVE and FD_CMD_RESTORE in hw/fdc.c

Per https://bugs.launchpad.net/qemu/+bug/424453 the correct values
for FD_CMD_SAVE is 0x2e and FD_CMD_RESTORE is 0x4e. Verified against
the Intel 82078 manual which can be found at:
http://wiki.qemu.org/Documentation/HardwareManuals page 22.

Signed-off-by: Jes Sorensen <Jes.Sorensen@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>