usb: gadget: ncm: Fix indentations in documentation of NCM section

Currently, the section of NCM which describes attributes are having wrong
indentation.

Fix this by following the correct format recommended.

Fixes: 1900daee

 ("usb: gadget: ncm: Add support to update wMaxSegmentSize via configfs")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Closes: https://lore.kernel.org/all/20240108160221.743649b5@canb.auug.org.au/
Signed-off-by: Udipto Goswami <quic_ugoswami@quicinc.com>
Link: https://lore.kernel.org/r/20240108132720.7786-1-quic_ugoswami@quicinc.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>