msm: ipa: enable hdr_metadata_reg_valid for usb

Set the hdr_metadata_reg_valid to true on endpoint
configuration when usb connected as rndis and ecm
protocol for IPA_CLIENT_USB_PROD pipe.

Change-Id: Ic08e95cdfdb72cbc8d915bde1f4b430c2edf7b81
Signed-off-by: Skylar Chang <chiaweic@codeaurora.org>