spdx30: Provide software_packageUrl field in SPDX 3.0 SBOM

Define var-SPDX_PACKAGE_URL to provide software_packageUrl field [1][2]
in SPDX 3.0 SBOM, support to override with package name
SPDX_PACKAGE_URL:<pkgname>

Currently, the format of purl is not defined in Yocto, set empty for now
until we have a comprehensive plan for what Yocto purls look like.
But users could customize their own purl by setting var-SPDX_PACKAGE_URL

[1] https://spdx.github.io/spdx-spec/v3.0.1/model/Software/Properties/packageUrl/
[2] https://spdx.github.io/spdx-spec/v3.0.1/annexes/pkg-url-specification/

(From OE-Core rev: c8e6953a0b6f59ffca994c440069db39e60b12d2)

Signed-off-by: Hongxu Jia <hongxu.jia@windriver.com>
Signed-off-by: Mathieu Dubois-Briand <mathieu.dubois-briand@bootlin.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/classes/create-spdx-3.0.bbclass

@@ -117,6 +117,11 @@ SPDX_PACKAGE_VERSION ??= "${PV}"
 SPDX_PACKAGE_VERSION[doc] = "The version of a package, software_packageVersion \
     in software_Package"
 
+SPDX_PACKAGE_URL ??= ""
+SPDX_PACKAGE_URL[doc] = "Provides a place for the SPDX data creator to record \
+the package URL string (in accordance with the Package URL specification) for \
+a software Package."
+
 IMAGE_CLASSES:append = " create-spdx-image-3.0"
 SDK_CLASSES += "create-spdx-sdk-3.0"
 

meta/lib/oe/spdx30_tasks.py

@@ -631,6 +631,14 @@ def create_spdx(d):
             set_var_field("SUMMARY", spdx_package, "summary", package=package)
             set_var_field("DESCRIPTION", spdx_package, "description", package=package)
 
+            if d.getVar("SPDX_PACKAGE_URL:%s" % package) or d.getVar("SPDX_PACKAGE_URL"):
+                set_var_field(
+                    "SPDX_PACKAGE_URL",
+                    spdx_package,
+                    "software_packageUrl",
+                    package=package
+                )
+
             pkg_objset.new_scoped_relationship(
                 [oe.sbom30.get_element_link_id(build)],
                 oe.spdx30.RelationshipType.hasOutput,