scripts/spdxcheck: Exclude config directories

Kernel configuration files like default configs are machine generated and
pretty useless outside of the kernel context.

Signed-off-by: Thomas Gleixner <[e-mail]>
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

scripts/spdxexclude

···
 # create lots of noise for no value
 LICENSES/
 license-rules.rst
+
+# Ignore config files and snippets. The majority is generated
+# by the Kconfig tools
+kernel/configs/
+arch/*/configs/