meta: set S from UNPACKDIR in recipes that use only local files

There is no need to have two assignments; also setting S from
UNPACKDIR (and not vice versa) is more logical as unpack
task comes first, and tasks that come after unpack use S to access
unpack results.

Also adjust reference test data in selftest/recipeutils to reflect changes in test recipes.

(From OE-Core rev: f64b7e5fb3181734c8dde87b27e872a026261a74)

Signed-off-by: Alexander Kanavin <alex@linutronix.de>
Signed-off-by: Mathieu Dubois-Briand <mathieu.dubois-briand@bootlin.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta-skeleton/recipes-kernel/hello-mod/hello-mod_0.1.bb

@@ -10,8 +10,7 @@ SRC_URI = "file://Makefile \
            file://COPYING \
           "
 
-S = "${WORKDIR}/sources"
-UNPACKDIR = "${S}"
+S = "${UNPACKDIR}"
 
 # The inherit of module.bbclass will automatically name module packages with
 # "kernel-module-" prefix as required by the oe-core build environment.

meta-skeleton/recipes-skeleton/hello-single/hello_1.0.bb

@@ -5,8 +5,7 @@ LIC_FILES_CHKSUM = "file://${COMMON_LICENSE_DIR}/MIT;md5=0835ade698e0bcf8506ecda
 
 SRC_URI = "file://helloworld.c"
 
-S = "${WORKDIR}/sources"
-UNPACKDIR = "${S}"
+S = "${UNPACKDIR}"
 
 do_compile() {
 	${CC} ${LDFLAGS} helloworld.c -o helloworld

meta-skeleton/recipes-skeleton/service/service_0.1.bb

@@ -9,8 +9,7 @@ SRC_URI = "file://skeleton \
 	   file://COPYRIGHT \
 	   "
 
-S = "${WORKDIR}/sources"
-UNPACKDIR = "${S}"
+S = "${UNPACKDIR}"
 
 do_compile () {
 	${CC} ${CFLAGS} ${LDFLAGS} ${S}/skeleton_test.c -o ${B}/skeleton-test

meta-skeleton/recipes-skeleton/useradd/useradd-example.bb

@@ -9,8 +9,7 @@ SRC_URI = "file://file1 \
            file://file3 \
            file://file4"
 
-S = "${WORKDIR}/sources"
-UNPACKDIR = "${S}"
+S = "${UNPACKDIR}"
 
 PACKAGES =+ "${PN}-user3"