radeonsi: fix memory leak and/or segfaults

Fix a stupid typo that could lead to memory
leaks and/or segfaults.

Signed-off-by: Christian König <deathsimple@vodafone.de>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>

src/gallium/drivers/radeonsi/radeonsi_pm4.c

@@ -119,7 +119,7 @@ void si_pm4_free_state(struct r600_context *rctx,
 	}
 
 	for (int i = 0; i < state->nbo; ++i) {
-		si_resource_reference(&state->bo[idx], NULL);
+		si_resource_reference(&state->bo[i], NULL);
 	}
 	FREE(state);
 }