cve-check: Modify judgment processing using "=" in version comparison

cve-check: Modify judgment processing using "=" in version comparison

Judgment processing of vulnerable using "=" compares characters as strings rather than numbers,
and misjudges "cases that do not match in strings but do match in numbers" as "Patched".
(e.g. PV = "1.2.0" and Vulnerabilities Affected Versions (registered with NVD) = "1.2")

Therefore, if the comparison operator used in the judgment processing of vulnerable is "=",
add numeric comparison processing.

Signed-off-by: Shinji Matsunaga <shin.matsunaga@fujitsu.com>
Signed-off-by: Shunsuke Tokumoto <s-tokumoto@fujitsu.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>