kernelscan: fix variable shadowing warning

Cppcheck is warning about variable name shadowing. Fix this by
renaming the top level variable 'patterns' to 'klog_patterns'.

Cleans up cppcheck warning:
src/utilities/kernelscan.c:352:16: style: Local variable 'patterns'
shadows outer variable [shadowVariable]
 klog_pattern *patterns;

src/utilities/kernelscan.c:113:22: note: Shadowed declaration
 static klog_pattern *patterns;

src/utilities/kernelscan.c:352:16: note: Shadow variable
 klog_pattern *patterns;

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Acked-by: Alex Hung <alex.hung@canonical.com>
Acked-by: Ivan Hu <ivan.hu@canonical.com>