drm/msm/dpu: Add callback function pointer check before its call

{
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "unaffected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "drivers/gpu/drm/msm/disp/dpu1/dpu_hw_interrupts.c"
                    ],
                    "versions": [
                        {
                            "version": "c929ac60b3ed34accd25a052a4833e418900f466",
                            "lessThan": "873f67699114452c2a996c4e10faac8ff860c241",
                            "status": "affected",
                            "versionType": "git"
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                        {
                            "version": "c929ac60b3ed34accd25a052a4833e418900f466",
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                            "versionType": "git"
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                            "lessThan": "530f272053a5e72243a9cb07bb1296af6c346002",
                            "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/gpu/drm/msm/disp/dpu1/dpu_hw_interrupts.c"
                    ],
                    "versions": [
                        {
                            "version": "5.19",
                            "status": "affected"
                        },
                        {
                            "version": "0",
                            "lessThan": "5.19",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.6.33",
                            "lessThanOrEqual": "6.6.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.9.4",
                            "lessThanOrEqual": "6.9.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.10",
                            "lessThanOrEqual": "*",
                            "status": "unaffected",
                            "versionType": "original_commit_for_fix"
                        }
                    ]
                }