package/patch: annotate CVE-2019-13638

GNU patch through 2.7.6 is vulnerable to OS shell command injection that
can be exploited by opening a crafted patch file that contains an ed
style diff payload with shell metacharacters. The ed editor does not
need to be present on the vulnerable system. This is different from
CVE-2018-1000156.

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>