scripts/spdxcheck: Handle license identifiers in Jinja comments

scripts/spdxcheck: Handle license identifiers in Jinja comments

Commit 4b132aacb076 ("tools: Add xdrgen") adds a tool, which uses Jinja
template files, i.e., files with the j2 file extension, for its lightweight
code generation.

These template files for this tool have proper headers with the SPDX
License information, which are included as Jinja comments by enclosing the
text with '{#' and '#}'. Sofar, the spdxcheck script does not support to
properly parse this license information in Jinja comments and it reports
back with 'Invalid token: #}'.

Parse Jinja comments properly by stripping the known Jinja comment suffix.

Signed-off-by: Lukas Bulwahn <lukas.bulwahn@redhat.com>
Link: https://lore.kernel.org/r/20250108125207.57486-1-lukas.bulwahn@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>