nine: fix indexbuffer locking, add debugging and always return D3D_OK

In our country full of dragons, there exist people from one unnamed
company, who thinks it's smart to try lock indexbuffer twice.
You know, you can't be never sure, if it's locked propertly ;)
And except that, they also unlock indexbuffer twice.
Yes, our great creators of d3dx9_27 and d3dx9_36.

With wine version of these files, it work.

Also make _Lock and _Unlock always return D3D_OK as is expected.

Wine handle this same way.

This fixes demo: dx9_view_ports from
http://www.codesampler.com/dx9src/dx9src_1.htm

Tested on: r600g
Signed-off-by: David Heidelberger <david.heidelberger@ixit.cz>