Bluetooth: MGMT: Protect mgmt_pending list with its own lock

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                    "vendor": "Linux",
                    "defaultStatus": "unaffected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "include/net/bluetooth/hci_core.h",
                        "net/bluetooth/hci_core.c",
                        "net/bluetooth/mgmt.c",
                        "net/bluetooth/mgmt_util.c",
                        "net/bluetooth/mgmt_util.h"
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{
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "affected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "include/net/bluetooth/hci_core.h",
                        "net/bluetooth/hci_core.c",
                        "net/bluetooth/mgmt.c",
                        "net/bluetooth/mgmt_util.c",
                        "net/bluetooth/mgmt_util.h"
                    ],
                    "versions": [
                        {
                            "version": "4.1",
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                        {
                            "version": "0",
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                        {
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                            "version": "6.12.34",
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                        {
                            "version": "6.16",
                            "lessThanOrEqual": "*",
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                            "versionType": "original_commit_for_fix"
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                    ]
                }