net/vpp: set vpp to last official release v19.04.2

Before this patch scripts/docs based on tip of 19.04 VPP stable branch,
because VPP 19.04.2 was not yet released at the time of implementation merge.

Now that VPP 19.04.2 was released, we change to actual release tag.
In order to prevent using untested commit, if new patches were to be merged
on top of VPP 19.04 stable branch.

Change-Id: Id3584a13c48eba25b061ae7a6fc51e477a6425c5
Signed-off-by: Tomasz Kulasek <tomaszx.kulasek@intel.com>
Signed-off-by: Tomasz Zawadzki <tomasz.zawadzki@intel.com>
Reviewed-on: https://review.gerrithub.io/c/spdk/spdk/+/463328
Reviewed-by: Jim Harris <james.r.harris@intel.com>
Reviewed-by: Ben Walker <benjamin.walker@intel.com>
Tested-by: SPDK CI Jenkins <sys_sgci@intel.com>

doc/vpp_integration.md

@@ -16,7 +16,7 @@ VPP [Quick Start Guide](https://wiki.fd.io/view/VPP).
 Clone and checkout VPP
 ~~~
 git clone https://gerrit.fd.io/r/vpp && cd vpp
-git checkout stable/1904
+git checkout v19.04.2
 ~~~
 
 Install VPP build dependencies

test/common/config/vm_setup.sh

@@ -237,7 +237,7 @@ function install_vpp()
             fi
         else
             git clone "${GIT_REPO_VPP}"
-            git -C ./vpp checkout stable/1904
+            git -C ./vpp checkout v19.04.2
 
             if [ "${OSID}" == 'fedora' ]; then
                 if [ ${OSVERSION} -eq 29 ]; then