mmc: Add new VUB300 USB-to-SD/SDIO/MMC driver

Add a driver for Elan Digital System's VUB300 chip which is a USB
connected SDIO/SDmem/MMC host controller.  A VUB300 chip enables a USB 2.0
or USB 1.1 connected host computer to use SDIO/SD/MMC cards without the
need for a directly connected, for example via PCI, SDIO host controller.

Signed-off-by: Anthony F Olech <tony.olech@elandigitalsystems.com>
[cjb: various punctuation and style fixes]
Tested-by: Chris Ball <cjb@laptop.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
diff --git a/MAINTAINERS b/MAINTAINERS
index 69f19f1..5891aef 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -6778,6 +6778,13 @@
 S:	Maintained
 F:	drivers/hwmon/vt8231.c
 
+VUB300 USB to SDIO/SD/MMC bridge chip
+M:	Tony Olech <tony.olech@elandigitalsystems.com>
+L:	linux-mmc@vger.kernel.org
+L:	linux-usb@vger.kernel.org
+S:	Supported
+F:	drivers/mmc/host/vub300.c
+
 W1 DALLAS'S 1-WIRE BUS
 M:	Evgeniy Polyakov <johnpol@2ka.mipt.ru>
 S:	Maintained