usb: xhci: Add Renesas R-Car xHCI driver

Add firmware V3, firmware loader and XHCI glue for the Renesas R-Car
Gen3 SoCs XHCI controller. Thus far only the R-Car Gen3 R8A7795 ES2.0+
and R8A7796 are supported.

Signed-off-by: Marek Vasut <marek.vasut+renesas@gmail.com>
Cc: Nobuhiro Iwamatsu <iwamatsu@nigauri.org>
Cc: Bin Meng <bmeng.cn@gmail.com>

Licenses/r8a779x_usb3.txt

@@ -0,0 +1,26 @@
+Copyright (c) 2014, Renesas Electronics Corporation
+All rights reserved.
+
+Redistribution and use in binary form, without modification, are permitted
+provided that the following conditions are met:
+
+1. Redistribution in binary form must reproduce the above copyright notice,
+   this list of conditions and the following disclaimer in the documentation
+   and/or other materials provided with the distribution.
+2. The name of Renesas Electronics Corporation may not be used to endorse or
+   promote products derived from this software without specific prior written
+   permission.
+3. Reverse engineering, decompilation, or disassembly of this software is
+   not permitted.
+
+THIS SOFTWARE IS PROVIDED "AS IS" AND RENESAS ELECTRONICS CORPORATION DISCLAIMS
+ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, AND
+NONINFRINGEMENT OF THIRD PARTY RIGHTS. IN NO EVENT SHALL RENESAS ELECTRONICS
+CORPORATION BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
+OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGE.