perl: run builds from a pristine source tree

Running builds from a previously used directory relies on correctness of
'make clean' or incremental 'make', and sadly perl (or perl-cross) does not have either.

The particularly nasty problem, currently occurring, is that sometimes, when reusing
a previous build, we arrive at a combination of timestamps in the tree,
where make becomes very confused, gets lost in its own rules and enters an infinite loop,
never figuring out what needs to be rebuild in what order. Worse, there is no reliable
trigger for this that was found, and any attempts to 'isolate the issue' haven't produced one.

Let's simply add a clean S/B separation for builds, and always run a build from a reproducible
set of files.

[YOCTO #14902]

(From OE-Core rev: 0919f5ec214594380eb5190b4878eadb30e3a471)

Signed-off-by: Alexander Kanavin <alex@linutronix.de>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/recipes-devtools/perl/perl_5.36.0.bb

@@ -28,7 +28,7 @@ SRC_URI:append:class-target = " \
 
 SRC_URI[perl.sha256sum] = "e26085af8ac396f62add8a533c3a0ea8c8497d836f0689347ac5abd7b7a4e00a"
 
-S = "${WORKDIR}/perl-${PV}"
+B = "${WORKDIR}/perl-${PV}-build"
 
 inherit upstream-version-is-even update-alternatives
 
@@ -48,7 +48,10 @@ export ENC2XS_NO_COMMENTS = "1"
 CFLAGS += "-D_GNU_SOURCE -D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64"
 
 do_configure:prepend() {
-    cp -rfp ${STAGING_DATADIR_NATIVE}/perl-cross/* ${S}
+    rm -rf ${B}
+    cp -rfp ${S} ${B}
+    cp -rfp ${STAGING_DATADIR_NATIVE}/perl-cross/* ${B}
+    cd ${B}
 }
 
 do_configure:class-target() {
@@ -116,7 +119,6 @@ print(datetime.fromtimestamp($SOURCE_DATE_EPOCH, timezone.utc).strftime('%a %b %
             ")"
         echo "#define PERL_BUILD_DATE \"$PERL_BUILD_DATE\"" >> config.h
     fi
-    oe_runmake clean
 }
 
 do_compile() {