Fixed undefined variable value with certain code paths.
Fixed undefined variable value with certain code paths.

In sentinelFlushConfig() fd could be undefined when the following if
statement was true:

        if (rewrite_status == -1) goto werr;

This could cause random file descriptors to get closed.

JackieXie168/redis,JackieXie168/redis,JackieXie168/redis,JackieXie168/redis