USB: update host controller Kconfig entries

The recent patches from Manjunath Goudar introduced two small
mistakes in the Kconfig help text for the new options. Let's
fix those and the other entries that have become stale over time.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>