log_strdup writes out of bounds of a strdup slab.
e.g: CONFIG_LOG_STRDUP_MAX_STRING=46 and
LOG_STRBUF_STR_SIZE=47 then in the line L:529
sdupl[LOG_STRBUF_STR_SIZE - 1] = '\0';
writes out of bounds because the available buffer space
is only 44 bytes (rounded up to 48 bytes and minus 4 bytes
for the allocated flag).
Signed-off-by: Johann Fischer <j.fischer@phytec.de>