[PATCH] sparse-annotate radiotap header

Document that all fields must be little endian.  Use annotated types
even in the comments.  Consistently use shorter type names (u8, s8).
Realign the comments.

Signed-off-by: Pavel Roskin <proski@gnu.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>