bpf: Reject key-less BTF for hash maps

{
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "unaffected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "kernel/bpf/hashtab.c"
                    ],
                    "versions": [
                        {
                            "version": "451a84a3ad3c897c03181af433e7c98640730f1f",
                            "lessThan": "54098e3fe34ec190bc256b338b9a93c7e2dc9354",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "51a17f0ce19c4ee2a25cf16c93490d509b1ebb0a",
                            "lessThan": "fa047f2a025003f5654ebd76539f16a6ead0401a",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "1df97a7453eec80c1912c2d0360290a3970a7671",
                            "lessThan": "7ca231252820c47aaec42a5db580db98f9b64724",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "1df97a7453eec80c1912c2d0360290a3970a7671",
                            "lessThan": "0895a0c0734703be5532f3883c42db95615fd98b",
                            "status": "affected",
                            "versionType": "git"
                        }
                    ]
                }

{
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "affected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "kernel/bpf/hashtab.c"
                    ],
                    "versions": [
                        {
                            "version": "7.0",
                            "status": "affected"
                        },
                        {
                            "version": "0",
                            "lessThan": "7.0",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "7.2.7",
                            "lessThanOrEqual": "7.2.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "7.3",
                            "lessThanOrEqual": "*",
                            "status": "unaffected",
                            "versionType": "original_commit_for_fix"
                        }
                    ]
                }