sys/log: Fix spurious uninitialized variable varning
GCC 7.3.1 complains about possible uinitialized 'rc' variable in
'shell_log_dump_entry' at 'if (rc < len) {` in optimized build.
This does not seem to be correct, but let's make it happy and
initialize 'rc'.
@@ -152,7 +152,7 @@ shell_log_dump_entry(struct log *log, struct log_offset *log_offset,
{
char data[128 + 1];
int dlen;
- int rc;
+ int rc = 0;
#if MYNEWT_VAL(LOG_VERSION) > 2
struct CborParser cbor_parser;
struct CborValue cbor_value;
