json-c: define CVE_VERSION

json-c: define CVE_VERSION

Recently NVD updated all CVEs for json-c and old fixed
cves are reported in some older yocto branches.
NVD match clause now includes full tag name including
date which is "greater" than tag without additional numbers.

Define CVE_VERSION identical to full tag also on master to
avoid future CVEs to be reported incorrectly.
Put it close to hash so recipe update patch includes this line.

Signed-off-by: Peter Marko <peter.marko@siemens.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>