sys/linux: add basic descriptions for BSG devices #16827

Job	Run time
dashboard	2m 38s
build	3m 45s
aux	4m 13s
arch (presubmit_arch_windows)	3m 49s
arch (presubmit_arch_openbsd)	4m 3s
arch (presubmit_arch_freebsd)	6m 17s
arch (presubmit_arch_darwin)	3m 44s
arch (presubmit_arch_netbsd)	4m 2s
arch (presubmit_arch_linux)	10m 17s
race	8m 41s
arch (presubmit_arch_executor)	3m 25s
race_dashboard	3m 20s
old	6m 45s
gvisor	3m 51s
	1h 8m 50s

Provide feedback