Input: fix accuracy of fixp-arith.h

Add the value of cos(90) = 0 to the table.  This also moves the results so
that sin(x) == sin(180-x) is true as expected.

Signed-off-by: Anssi Hannula <anssi.hannula@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>