platform/chrome: cros_ec_proto: don't show MKBP version if unsupported

stable inclusion
from stable-v5.10.138
commit 0a0da5ef5b4e92324fdbd2d0c24d24a79d2f87f4
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I60QFD

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=0a0da5ef5b4e92324fdbd2d0c24d24a79d2f87f4



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[ Upstream commit b36f0643 ]

It wrongly showed the following message when it doesn't support MKBP:
"MKBP support version 4294967295".

Fix it.

Reviewed-by: Guenter Roeck <groeck@chromium.org>
Signed-off-by: Tzung-Bi Shih <tzungbi@kernel.org>
Link: https://lore.kernel.org/r/20220609084957.3684698-14-tzungbi@kernel.org


Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>
Reviewed-by: Wei Li <liwei391@huawei.com>