anv: Drop I915_EXEC_CONSTANTS_REL_GENERAL from execbuf.

anv: Drop I915_EXEC_CONSTANTS_REL_GENERAL from execbuf.

The kernel used to have execbuf parameters to program the INSTPM bit
for whether 3DSTATE_CONSTANT_* should be relative to dynamic state
base address or an absolute address.  However, they never worked in
the presence of hardware contexts, so I deleted them a while back.

It doesn't make sense to set this flag, as it doesn't exist anymore.
It also never did anything anyway - the flag is zero, so |'ing it in
did nothing.  The default is relative anyway.

Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>