pseries: Update SLOF firmware image

This has reworked USB OHCI and adds support of USB EHCI,
VIRTIO-SCSI and various fixes (IBM VSCSI, VGA and more).

The full list of fixes is:
*  usb-ohci: Convert td-phys every time to td-virt
*  usb-storage: Fix cbwflags field
*  Add -fno-strict-aliasing in global CFLAGS
*  usb: fix various issues found with js2x
*  Move hex64-{decode,encode}-unit to node.fs
*  usb: Use separate in-memory endian swap
*  usb-ohci: collect TDs from done list
*  js2x: more fixes
*  js2x: Fix build of takeover image
*  js2x: use new usb stack
*  usb-ohci: Use proper memory barriers always
*  usb: Fix a couple of warnings
*  Fix $cat-instance-unit
*  Cache phandle of /chosen
*  Use root.fs on qemu as well
*  usb-ehci: Add ehci handshake
*  usb: add mb for write accessors
*  usb-ohci: add missing memory barriers
*  usb-ohci: suspend the controller in exit code path
*  usb-ohci: Add a reset when closing the OHCI
*  usb: Use proper accessors for MMIO and separate in-memory endian swap
*  Use a global definition of sync() and mb()
*  net-snk: Remove exception handling
*  usb: unmap buffers
*  slof: call quiesce on closing of stdin
*  usb-kbd: accept "s" to drop to OF prompt
*  USB storage driver
*  usb-ohci: add Bulk transfer support
*  usb-ehci: Add bulk support
*  usb-core: add usb bulk support
*  USB generic hub device driver
*  usb-ehci: setup new device
*  usb-ehci: Check ehci ports
*  usb-ehci: initialize controller
*  USB keyboard driver
*  usb-core: setup new device
*  usb-core: create dev pool allocation
*  usb-ohci: implement ohci send control
*  usb-core: usb send control
*  usb-core: implement usb_{get,put}_pipe routines
*  usb-ohci: allocate pipe pool
*  usb-ohci: reset, init and check-ports
*  Add standard header stdbool.h
*  usb-slof: forth support routines for C
*  usb-ehci: Add USB EHCI skeleton
*  usb-core: Add register accessor functions
*  Use __builtin_bswap routines for endianness swapping
*  usb-core: hcd registration and query routines
*  usb-core: adding generic dev-hci.fs
*  usb-core: registration and makefiles
*  Add new USB code
*  Remove old usb code
*  vga: fix hcall-invert-screen and hcall-blink-screen
*  Enumerate disk/cdrom aliases for multiple disks or cdroms
*  scsi: unify scsi probing code
*  vscsi: generalizing probe code
*  virtio-scsi: iterate through targets
*  scsi: unify and use make-disk-alias
*  nvram: remove unnecessary prints
*  Add hack to client interface finddevice of "/memory"
*  scsi: Fix cdrom boot crash when no medium present
*  Look for /memory@0, not just /memory
*  Fix instance>qname crashing when displaying instance arguments
*  Fix js2x build
*  scsi-disk: Bound check read-blocks
*  Fix off by one error in scsi-disk get-capacity
*  scsi: fix report-luns handling
*  SLOF: virtio-scsi block driver code
*  scsi: Move bits of vio-vscsi.fs to a common helpers file
*  scsi: Move scsi-disk.fs to a generic place
*  SLOF: virtio-scsi helper routines
*  SLOF: virtio-scsi - add pci device file
*  iso9660: Don't constantly reallocate the read buffer
*  vscsi: Sanitize interface between scsi-disk.fs and vio-vscsi.fs
*  vio-vscsi: Rework vio-vscsi support
*  virtio: Add a virtio-set-qaddr helper
*  disk-label: Allocate 4096 bytes for 4k block devices
*  disk-label: Increase the max size of the PReP boot partition
*  Make load-base a real environment variable
*  vio-vscsi: Switch to using a wildcard "disk" node and make scsi-disk generic
*  Fix disk-label package to use proper instance path
*  Increase size of catpad
*  Fix instance>path to contain unit address for wildcard nodes
*  Fix handling of wildcard nodes in open-dev
*  vio-vscsi: Get CRQ on open and release on close

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Alexander Graf <agraf@suse.de>