Errors from staticcheck:
pkg/volume/azure_dd/azure_common.go:68:2: var winDiskNumFormat is unused (U1000)
pkg/volume/csi/csi_block.go:97:2: field volumeInfo is unused (U1000)
pkg/volume/csi/csi_block_test.go:56:6: func prepareBlockUnmapperTest is unused (U1000)
pkg/volume/csi/csi_client.go:108:2: const initialDuration is unused (U1000)
pkg/volume/csi/csi_client.go:109:2: const factor is unused (U1000)
pkg/volume/csi/csi_client.go:110:2: const steps is unused (U1000)
pkg/volume/csi/csi_client_test.go:83:8: this value of err is never used (SA4006)
pkg/volume/csi/csi_mounter.go:76:2: field options is unused (U1000)
pkg/volume/csi/csi_mounter_test.go:454:13: this value of err is never used (SA4006)
pkg/volume/csi/csi_plugin_test.go:766:16: this value of err is never used (SA4006)
pkg/volume/csi/csi_plugin_test.go:861:13: this value of err is never used (SA4006)
pkg/volume/csi/csi_plugin_test.go:1186:13: this value of err is never used (SA4006)
pkg/volume/csi/csi_plugin_test.go:1249:13: this value of err is never used (SA4006)
pkg/volume/csi/csi_test.go:305:5: the goroutine calls T.Fatalf, which must be called in the same goroutine as the test (SA2002)
pkg/volume/flexvolume/probe_test.go:67:10: this value of err is never used (SA4006)
pkg/volume/iscsi/iscsi_test.go:95:2: field attachCalled is unused (U1000)
pkg/volume/iscsi/iscsi_test.go:96:2: field detachCalled is unused (U1000)
pkg/volume/iscsi/iscsi_test.go:501:24: this value of err is never used (SA4006)
pkg/volume/iscsi/iscsi_util_test.go:159:2: this value of exist is never used (SA4006)
pkg/volume/local/local.go:351:57: argument devicePath is overwritten before first use (SA4009)
pkg/volume/plugins_test.go:119:2: this value of plug is never used (SA4006)
pkg/volume/plugins_test.go:125:2: this value of plug is never used (SA4006)
pkg/volume/quobyte/quobyte.go:474:23: this result of append is never used, except maybe in other appends (SA4010)
pkg/volume/quobyte/quobyte.go:477:23: this result of append is never used, except maybe in other appends (SA4010)
pkg/volume/quobyte/quobyte.go:480:23: this result of append is never used, except maybe in other appends (SA4010)
pkg/volume/rbd/rbd.go:886:2: field adminSecret is unused (U1000)
pkg/volume/rbd/rbd.go:887:2: field adminID is unused (U1000)
pkg/volume/rbd/rbd.go:888:2: field imageFormat is unused (U1000)
pkg/volume/rbd/rbd.go:889:2: field imageFeatures is unused (U1000)
pkg/volume/storageos/storageos.go:302:2: field secretName is unused (U1000)
pkg/volume/storageos/storageos_util_test.go:43:2: field apiAddr is unused (U1000)
pkg/volume/storageos/storageos_util_test.go:44:2: field apiUser is unused (U1000)
pkg/volume/storageos/storageos_util_test.go:45:2: field apiPass is unused (U1000)
pkg/volume/storageos/storageos_util_test.go:46:2: field apiVersion is unused (U1000)
pkg/volume/util/atomic_writer_test.go:756:49: argument err is overwritten before first use (SA4009)
pkg/volume/util/fsquota/common/quota_linux_common.go:37:2: const acct is unused (U1000)
pkg/volume/util/fsquota/common/quota_linux_common.go:38:2: const enforcing is unused (U1000)
pkg/volume/util/fsquota/project.go:168:31: identical expressions on the left and right side of the '==' operator (SA4000)
pkg/volume/util/fsquota/quota_linux.go:306:50: argument poduid is overwritten before first use (SA4009)
pkg/volume/util/fsquota/quota_linux_test.go:558:16: this value of err is never used (SA4006)
pkg/volume/util/subpath/subpath_linux.go:232:81: argument err is overwritten before first use (SA4009)
pkg/volume/util/subpath/subpath_linux_test.go:579:73: argument err is overwritten before first use (SA4009)
This patch cleans up pkg/util/mount/* and pkg/util/volume/* to always
use filepath.Join instead of path.Join. filepath.Join is preferred
because path.Join can have issues on Windows.
