usbutils: avoid dependency on bash

usbutils: avoid dependency on bash

By virtue of having #!/bin/bash, the usb-devices script declared that it
requires bash, however manual examination, checkbashisms and tests with
dash and busybox show that it doesn't contain any bashisms, so change
the script's header and remove the RDEPENDS on bash.

Additionally, update-usbids.sh was manually checked for bashisms, run
through checkbashisms and tested with busybox (although it did not have
a bash-specific header).

(From OE-Core rev: 651b223c5fc93c7504e304e954b9ae4640ed47c6)

Signed-off-by: Paul Eggleton <paul.eggleton@linux.intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>