3rdparty/lib{hwbase,gfxinit}: Update to latest master

Simplifies our C interface function gma_gfxinit(), due to the following
changes:

* *libgfxinit* knows about the underlying PCI device now and can
  probe MMIO addresses by itself.
* The framebuffer mapping is now completely handled inside the
  library where we validate that we neither overflow
  - the stolen memory,
  - the GTT address space, the GTT itself nor
  - the aperture window (i.e. resource2 of the PCI device)
    that we use to access the framebuffer.

Other changes:

* Fixes and a quirk for DP training.
* Fix for DP-VGA adapters that report an analog display in EDID.
* Fixes for Skylake support with coreboot.
* DDI Buffer drive-strength configuration for Haswell, Broadwell and
  Skylake.
* `gfx_test` can now be run from X windows (with glitches).
* Compatibility with GCC 7 and SPARK GPL 2017.

TEST=Booted lenovo/t420 and verified that everything works as usual.

Change-Id: I001ba973d864811503410579fd7ad55ab8612759
Signed-off-by: Nico Huber <nico.h@gmx.de>
Reviewed-on: https://review.coreboot.org/20606
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Arthur Heymans <arthur@aheymans.xyz>

Documentation/gfx/libgfxinit.md

@@ -39,22 +39,13 @@ GMA: Hook-up in Chipset Initialization
 Both configurations described above implement a procedure
 `GMA.gfxinit()`:
 
-    procedure gfxinit
-      (mmio_base   : in     word64;
-       linear_fb   : in     word64;
-       phys_fb     : in     word32;
-       lightup_ok  :    out int);
+    procedure gfxinit (lightup_ok : out int);
 
 This procedure is exported as the C function `gma_gfxinit()` as
 follows:
 
-    void gma_gfxinit(uint64_t mmio_base, uint64_t linear_fb,
-                     uint32_t phys_fb, int *lightup_ok);
+    void gma_gfxinit(int *lightup_ok);
 
-* `mmio_base`:  the base address of the GMA's MMIO resource
-* `linear_fb`:  the base address of the GMA's GTT window resource
-* `phys_fb`:    the physical address where the framebuffer should be
-                stored (usually the GMA's stolen memory)
 * `lightup_ok`: returns whether the initialization succeeded `1` or
                 failed `0`. Currently, only the case that no display
                 could be found counts as failure. A failure at a la-