MAINTAINERS: add usb raw gadget entry

Add myself (using the personal email address) as a reviewer for the
USB Raw Gadget driver.

Acked-by: Andrey Konovalov <andreyknvl@gmail.com>
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Link: https://lore.kernel.org/r/245047b3fffaf5c0b791ed226d1ea272b2aef031.1605060950.git.andreyknvl@google.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>