i965: Switch ip_record to the non-zeroing allocator.

All member variables of ip_record are already being initialized from
its constructor, it's not necessary to use rzalloc to allocate its
memory, and doing so makes it more likely that we will start relying
on the allocator to zero out all memory if the class is ever extended
with new member variables.

That's bad because it ties objects to some specific allocation scheme,
and gives unpredictable results when an object is created with a
different allocator -- Stack allocation, array allocation, or
aggregation inside a different object are some of the useful
possibilities that come to my mind.

Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>

src/mesa/drivers/dri/i965/brw_fs.h

@@ -112,7 +112,7 @@ static const fs_reg reg_null_d(ARF, BRW_ARF_NULL, BRW_REGISTER_TYPE_D);
 
 class ip_record : public exec_node {
 public:
-   DECLARE_RZALLOC_CXX_OPERATORS(ip_record)
+   DECLARE_RALLOC_CXX_OPERATORS(ip_record)
 
    ip_record(int ip)
    {