Bitfields for OpenHCI "HcBulkHeadED"/"HcBulkCurrentED" register:
Bit(s)	Description	)
 31-4	physical address of first/current Endpoint Descriptor in the Bulk
	  list (bits 31-4)
 3-0	reserved (0)
Note:	HcBulkCurrentED is set to 0000000h to indicate the end of the Bulk
	  list
SeeAlso: #00902,#00908,#00910