Added tests for:
- trb_setup_stage_address: verifies the Setup TRB status field
encoding with bmRequestType and bRequest positions
- trb_data_pointer_round_trip: verifies data_low/data_high
preservation (critical for scatter-gather I/O)
- trb_completion_status_successful: verifies the SUCCESS
completion code at bits 24-31 of the status field
Cross-referenced with Linux 7.1 drivers/usb/host/xhci.h
TRB_COMP_USB_SUCCESS and drivers/usb/host/xhci-ring.c
setup_bmRequestType().
Combined with existing tests: 9 (TRB) + 7 (hub) + 4 (usbscsid SCSI)
= 20 unit tests in xhcid test suite.
Resolves IMPROVEMENT-PLAN §4.2: Add TRB encoding/decoding tests.
Red Bear OS
52daa468b8