usb: host: ehci.h: fix single statement macros

Don't use the 'do {} while (0)' wrapper in a single statement macro.

Caught by checkpatch: "WARNING: Single statement macros should not
use a do {} while (0) loop"

Signed-off-by: Geyslan G. Bem <geyslan@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>