misc: nsm: only unlock nsm_dev on post-lock error paths

{
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "unaffected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "drivers/misc/nsm.c"
                    ],
                    "versions": [
                        {
                            "version": "b9873755a6c8ccfce79094c4dce9efa3ecb1a749",
                            "lessThan": "4aa3f7d48e91eb74a363c1b4d7dbdd28f5b341fb",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "b9873755a6c8ccfce79094c4dce9efa3ecb1a749",
                            "lessThan": "8f068342096b027181b168d91fef7ac7a2c64b25",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "b9873755a6c8ccfce79094c4dce9efa3ecb1a749",
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                        },
                        {
                            "version": "b9873755a6c8ccfce79094c4dce9efa3ecb1a749",
                            "lessThan": "ce1fed11d18e163baf7f875152a33bf80f625c1a",
                            "status": "affected",
                            "versionType": "git"
                        }
                    ]
                }

{
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "affected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "drivers/misc/nsm.c"
                    ],
                    "versions": [
                        {
                            "version": "6.8",
                            "status": "affected"
                        },
                        {
                            "version": "0",
                            "lessThan": "6.8",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.12.101",
                            "lessThanOrEqual": "6.12.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.18.42",
                            "lessThanOrEqual": "6.18.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "7.1.6",
                            "lessThanOrEqual": "7.1.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "7.2",
                            "lessThanOrEqual": "*",
                            "status": "unaffected",
                            "versionType": "original_commit_for_fix"
                        }
                    ]
                }