recipes: Start WORKDIR -> UNPACKDIR transition

Replace references of WORKDIR with UNPACKDIR where it makes sense to do
so in preparation for changing the default value of UNPACKDIR.

Signed-off-by: Khem Raj <raj.khem@gmail.com>

meta-oe/recipes-devtools/dnf-plugin-tui/dnf-plugin-tui_1.4.bb

@@ -24,7 +24,7 @@ do_install:append() {
 
 do_install:append:class-target() {
     install -d ${D}${sysconfdir}/yum.repos.d
-    install -m 0644 ${WORKDIR}/oe-remote.repo.sample ${D}${sysconfdir}/yum.repos.d
+    install -m 0644 ${UNPACKDIR}/oe-remote.repo.sample ${D}${sysconfdir}/yum.repos.d
 }
 
 do_install:append:class-nativesdk() {