luaRedisGenericCommand(): log error at WARNING level when re-entered.
luaRedisGenericCommand(): log error at WARNING level when re-entered.

Rationale is that when re-entering, it is likely due to Lua debugging
hooks. Returning an error will be ignored in most cases, going totally
unnoticed. With the log at least we leave a trace.

Related to issue #2302.

ScottKaiGu/redis,ScottKaiGu/redis,ideaar/redis,LittlePeng/redis,miminus/redis,jaambee/redis,miminus/redis,jaambee/redis,hanmichael/redis,Jonavin/redis,adamweixuan/redis,laurencee/redis,laurencee/redis,ideaar/redis,janeasystems/redis,liqiang199105/redis,jaambee/redis,jqk6/redis,alpha8/redis,adamweixuan/redis,Cybermaxs/redis,laurencee/redis,jacklee0810/redis,kolonse/redis,alpha8/redis,quangnguyen90/redis,enginekit/redis,jacklee0810/redis,kolonse/redis,Cybermaxs/redis,ScottKaiGu/redis,Jonavin/redis,janeasystems/redis,jaambee/redis,Jonavin/redis,jacklee0810/redis,Cybermaxs/redis,janeasystems/redis,kolonse/redis,Jonavin/redis,kts12345/redis,jqk6/redis,ScottKaiGu/redis,kts12345/redis,kolonse/redis,liqiang199105/redis,upsoft/redis,kts12345/redis,ScottKaiGu/redis,upsoft/redis,janeasystems/redis,laurencee/redis,miminus/redis,Cybermaxs/redis,janeasystems/redis,enginekit/redis,enginekit/redis,liqiang199105/redis,ideaar/redis,liqiang199105/redis,hanmichael/redis,kts12345/redis,Jonavin/redis,hanmichael/redis,damy/redis,alpha8/redis,Cybermaxs/redis,upsoft/redis,liqiang199105/redis,LittlePeng/redis,kts12345/redis,damy/redis,LittlePeng/redis,jacklee0810/redis,alpha8/redis,quangnguyen90/redis,jaambee/redis,damy/redis,damy/redis,enginekit/redis,ideaar/redis,damy/redis,enginekit/redis,alpha8/redis,adamweixuan/redis,adamweixuan/redis,hanmichael/redis,laurencee/redis,upsoft/redis,ideaar/redis,miminus/redis,quangnguyen90/redis,hanmichael/redis,upsoft/redis,quangnguyen90/redis,jqk6/redis,jacklee0810/redis,quangnguyen90/redis,jqk6/redis,kolonse/redis,adamweixuan/redis,jqk6/redis,miminus/redis