staging: vt665x: fix alignment constraints

staging: vt665x: fix alignment constraints

multiple structures contains a ieee80211_rts structure, which is required to
have at least two byte alignment, but are annotated with a __packed attribute
to force single-byte alignment:

staging/vt6656/rxtx.h:98:1: warning: alignment 1 of 'struct vnt_rts_g' is less than 2 [-Wpacked-not-aligned]
staging/vt6656/rxtx.h:106:1: warning: alignment 1 of 'struct vnt_rts_ab' is less than 2 [-Wpacked-not-aligned]
staging/vt6656/rxtx.h:116:1: warning: alignment 1 of 'struct vnt_cts' is less than 2 [-Wpacked-not-aligned]

I see no reason why the structure itself would be misaligned, and all members
have at least two-byte alignment within the structure, so use the same
constraint on the sturcture itself.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/20210204162731.3132069-1-arnd@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>