i965: Rename brw_upload_item_data to brw_alloc_item_data
i965: Rename brw_upload_item_data to brw_alloc_item_data

and simplify the interface to take directly the size and to return
the offset. The routine does nothing more than allocate, it doesn't
upload anything.

Reviewed-by: Anuj Phogat <e2026475996c48f0b97fd37e84129b3912980428@gmail.com>
Reviewed-by: Kenneth Graunke <bd2562f754ec92342f93f61c25d731e290a2ffa8@whitecape.org>
Signed-off-by: Topi Pohjolainen <749697f19798b7f640b17221fd283b903825f071@intel.com>

metora/MesaGLSLCompiler,metora/MesaGLSLCompiler,metora/MesaGLSLCompiler