verify_prereqs doesn't special-case on 'clean' arg

update docs and invocation accordingly

build/common.sh

@@ -114,10 +114,6 @@ readonly KUBE_ADDON_PATHS=(
 # Verify that the right utilities and such are installed for building Kube.  Set
 # up some dynamic constants.
 #
-# Args:
-#   $1 The type of operation to verify for.  Only 'clean' is supported in which
-#   case we don't verify docker.
-#
 # Vars set:
 #   KUBE_ROOT_HASH
 #   KUBE_BUILD_IMAGE_TAG

build/make-clean.sh

@@ -22,6 +22,6 @@ set -o pipefail
 KUBE_ROOT=$(dirname "${BASH_SOURCE}")/..
 source "$KUBE_ROOT/build/common.sh"
 
-kube::build::verify_prereqs clean
+kube::build::verify_prereqs
 kube::build::clean_output
 kube::build::clean_images