staging: rtl8192u: rename struct name _rt_firmare_seg_container

Rename struct _rt_firmare_seg_container to _fw_seg_container to match
the typedef name of this structure. Also removes the spelling mistake
of 'firmare'.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>