mesa: reset offset/size to 0 when removing atomic binding
mesa: reset offset/size to 0 when removing atomic binding

Similar to commit dd9d2963d6 (mesa: AtomicBufferBindings should be
initialized to zero.), we should reset these to zero when unbinding.
This fixes a number of dEQP failures due to cross-test pollution. The
tests properly unbound everything, but when querying the values again,
the expectation was that they would be 0.

Signed-off-by: Ilia Mirkin <bcbbb7aa705ec3a5fc5824c01a845186c3d62fca@alum.mit.edu>
Reviewed-by: Brian Paul <3cb4e1df5ec4da2c7c4af7c52cec8cf340a55a10@vmware.com>
Reviewed-by: Francisco Jerez <5906ff32bdd9fd8db196f6ba5ad3afd6f9257ea5@riseup.net>

metora/MesaGLSLCompiler,metora/MesaGLSLCompiler,metora/MesaGLSLCompiler