connman: fix CVE-2021-26675, CVE-2021-26676

A stack-based buffer overflow in dnsproxy in ConnMan before 1.39
could be used by network adjacent attackers to execute code.

gdhcp in ConnMan before 1.39 could be used by network-adjacent.
attackers to leak sensitive stack information, allowing further
exploitation of bugs in gdhcp.

References:
https://nvd.nist.gov/vuln/detail/CVE-2021-26675
https://nvd.nist.gov/vuln/detail/CVE-2021-26676

Upstream patches:
https://git.kernel.org/pub/scm/network/connman/connman.git/commit/?id=e4079a20f617a4b076af503f6e4e8b0304c9f2cb
https://git.kernel.org/pub/scm/network/connman/connman.git/commit/?id=58d397ba74873384aee449690a9070bacd5676fa
https://git.kernel.org/pub/scm/network/connman/connman.git/commit/?id=a74524b3e3fad81b0fd1084ffdf9f2ea469cd9b1



Signed-off-by: Catalin Enache <catalin.enache@windriver.com>
Signed-off-by: Randy MacLeod <Randy.MacLeod@windriver.com>
Signed-off-by: Steve Sakoman <steve@sakoman.com>