count device diff1 shares

cgminer.c

@@ -4186,6 +4186,7 @@ bool test_nonce(struct work *work, uint32_t nonce)
 bool submit_nonce(struct thr_info *thr, struct work *work, uint32_t nonce)
 {
 	total_diff1++;
+	thr->cgpu->diff1++;
 	work->pool->diff1++;
 
 	/* Do one last check before attempting to submit the work */

miner.h

@@ -396,6 +396,7 @@ struct cgpu_info {
 	int gpu_powertune;
 	float gpu_vddc;
 #endif
+	int diff1;
 	int last_share_pool;
 	time_t last_share_pool_time;