src/meta-openembedded:memcached: ignore disputed CVE-2022-26635

Per [1] this is a problem of applications using memcached inproperly.

This should not be a CVE against php-memcached, but for whatever
software the issue was actually found in. php-memcached and
libmemcached provide a VERIFY_KEY flag if they're too lazy to
filter untrusted user input.

[1] php-memcached-dev/php-memcached#519

Signed-off-by: Peter Marko <peter.markosiemens.com>
Signed-off-by: Khem Raj <raj.khemgmail.com>