st/nine: Lock the entire buffer in some cases.

st/nine: Lock the entire buffer in some cases.

Previously we had already found that for
MANAGED buffers the buffer started dirty
(which meant all writes out of bound
before the first draw call using the
buffer have to be taken into account).

Possibly it is the same for the other types of buffers.
For now always lock the entire buffer (starting from the offset)
for these (except for DYNAMIC buffers, which might hurt
performance too much).

Fixes: https://github.com/iXit/Mesa-3D/issues/301
Signed-off-by: Axel Davy <davyaxel0@gmail.com>