feat(driver/kubernetes): support mount buildkit.toml and qemu installing

Signed-off-by: Morlay <morlay.null@gmail.com>

go.mod

@@ -1,10 +1,9 @@
 module github.com/docker/buildx
 
-go 1.13
+go 1.16
 
 require (
 	github.com/agl/ed25519 v0.0.0-20170116200512-5312a6153412 // indirect
-	github.com/bitly/go-hostpool v0.0.0-20171023180738-a3a6125de932 // indirect
 	github.com/bugsnag/bugsnag-go v1.4.1 // indirect
 	github.com/bugsnag/panicwrap v1.2.0 // indirect
 	github.com/cenkalti/backoff v2.1.1+incompatible // indirect
@@ -12,7 +11,6 @@ require (
 	github.com/compose-spec/compose-go v0.0.0-20210729195839-de56f4f0cb3c
 	github.com/containerd/console v1.0.2
 	github.com/containerd/containerd v1.5.5
-	github.com/denisenkom/go-mssqldb v0.0.0-20190315220205-a8ed825ac853 // indirect
 	github.com/docker/cli v20.10.7+incompatible
 	github.com/docker/compose-on-kubernetes v0.4.19-0.20190128150448-356b2919c496 // indirect
 	github.com/docker/distribution v2.7.1+incompatible
@@ -22,7 +20,6 @@ require (
 	github.com/docker/libtrust v0.0.0-20150526203908-9cbd2a1374f4 // indirect
 	github.com/docker/spdystream v0.0.0-20181023171402-6480d4af844c // indirect
 	github.com/elazarl/goproxy v0.0.0-20191011121108-aa519ddbe484 // indirect
-	github.com/erikstmartin/go-testdb v0.0.0-20160219214506-8d10e4a1bae5 // indirect
 	github.com/fvbommel/sortorder v1.0.1 // indirect
 	github.com/gofrs/flock v0.7.3
 	github.com/gofrs/uuid v3.3.0+incompatible // indirect
@@ -33,10 +30,7 @@ require (
 	github.com/hashicorp/hcl/v2 v2.8.2
 	github.com/jinzhu/gorm v1.9.2 // indirect
 	github.com/jinzhu/inflection v0.0.0-20180308033659-04140366298a // indirect
-	github.com/jinzhu/now v1.0.0 // indirect
 	github.com/kardianos/osext v0.0.0-20190222173326-2bc1f35cddc0 // indirect
-	github.com/lib/pq v1.10.0 // indirect
-	github.com/mattn/go-sqlite3 v1.10.0 // indirect
 	github.com/moby/buildkit v0.8.2-0.20210702160134-1a7543a10527
 	github.com/opencontainers/go-digest v1.0.0
 	github.com/opencontainers/image-spec v1.0.1