Conflicts:
	nuttx/include/nuttx/usb/usbhost.h

STM32 F1 RTC Counter:  Now need to enable backup domain write access when setting the time.  From Darcy Gong

Bring in USB hub-related files from https://github.com/kaushalparikh/nuttx.  This is the work of Kaushal Parikh.  This initial commit is incomplete.  This is quite a bit more hub logic that needs to come in before the port is complete.

Fix an error introduced into stm32_pwr_enablebkp().  That function must preserve the previous state of backup domain access on return.

STM32F429i Disco: (1) Fix a bad return value if the LCD driver is already initialized. (2) The LCD driver initialization is now performed during the early boot sequence.  (3) Increased the size of the message queue from 32 to 64 in the lcd configuration.  From Marco, ocram.lhark@yahoo.com.