USB: Minimize delays involved in root hub initialization during HNP

Host controller driver may register root hub during HNP while
becoming B-Host.  Remove delays involved in debouncing and
applying port power.  This helps B-device to meet TB_ACON_BSE0
timing parameter and A-device will not find bus idle for longer
than TA_BIDL_ADIS.

Change-Id: Ib5df6417b10c6bde5bf5b9fd688c13a305ce7a4d
Signed-off-by: Pavankumar Kondeti <pkondeti@codeaurora.org>