mesa: use simple_mtx_t for TexMutex (v2)
change mtx_recursive -> mtx_plain, there's no recursive locking
Let's try this again! This was originally landed as f6abb344 ("mesa: use simple_mtx_t for TexMutex") and then reverted with 781c0eaf ("Revert "mesa: use simple_mtx_t for TexMutex"") because it broke i965. Now that i965 is no longer in the tree, we can restore it.
Acked-By: Mike Blumenkrantz michael.blumenkrantz@gmail.com (v1) Reviewed-by: Timothy Arceri tarceri@itsqueeze.com (v1) Reviewed-by: Kristian H. Kristensen hoegsberg@google.com (v1)