kernel-devsrc: check for localversion files in the kernel source tree

localversion files are ignored. This might lead to a bad version magic when
building out-of-tree modules via SDK.
(Backport from master https://git.yoctoproject.org/cgit/cgit.cgi/poky/commit/meta/recipes-kernel/linux/kernel-devsrc.bb?id=59fcee90de0cbb5b6b8333ab2b0e36214b174e52)

(From OE-Core rev: 85da4ccfff2103815eb3cd9a0b0f1af122b05567)

Signed-off-by: Christian Thaler <christian.thaler@tes-dst.com>
Signed-off-by: Armin Kuster <akuster808@gmail.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/recipes-kernel/linux/kernel-devsrc.bb

@@ -62,6 +62,12 @@ do_install() {
 	cd ${S}
 	cp --parents $(find  -type f -name "Makefile*" -o -name "Kconfig*") $kerneldir/build
 	cp --parents $(find  -type f -name "Build" -o -name "Build.include") $kerneldir/build
+
+	# Copy localversion file if any to keep correct version magic after
+	# modules_prepare.
+	if [ -f *localversion* ]; then
+	    cp *localversion* $kerneldir/build
+	fi
     )
 
     # then drop all but the needed Makefiles/Kconfig files
@@ -213,6 +219,9 @@ do_install() {
 
         # required to build scripts/selinux/genheaders/genheaders
         cp -a --parents security/selinux/include/* $kerneldir/build/
+
+	# copy any localversion files
+	cp -a localversion* $kerneldir/build/ 2>/dev/null || :
     )
 
     # Make sure the Makefile and version.h have a matching timestamp so that