toolchain: copy_toolchain_lib_root: copy symlinks instead of recreating them

copy_toolchain_lib_root handles symlinks by recreating them, disregarding
the original destination and assuming the destination is in the same
directory as the link itself.
When a library link points to the real library file in another directory,
for example:
    usr/lib/octeon2/libcrypt.so -> ../../../lib32/octeon2/libcrypt.so.1
then the link created by copy_toolchain_lib_root is broken.

It is more robust to copy the symlink to keep the destination intact. The
destination path should be present, possibly through other symbolic links.

Signed-off-by: Thomas De Schampheleire <thomas.de_schampheleire@nokia.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

toolchain/helpers.mk

@@ -19,8 +19,7 @@ copy_toolchain_lib_root = \
 			LIBNAME=`basename $${LIBPATH}`; \
 			rm -fr $(TARGET_DIR)/$${DESTDIR}/$${LIBNAME}; \
 			if test -h $${LIBPATH} ; then \
-				LINKTARGET=`readlink $${LIBPATH}` ; \
-				ln -sf `basename $${LINKTARGET}` $(TARGET_DIR)/$${DESTDIR}/$${LIBNAME} ; \
+				cp -d $${LIBPATH} $(TARGET_DIR)/$${DESTDIR}/$${LIBNAME}; \
 				LIBPATH="`readlink -f $${LIBPATH}`"; \
 			elif test -f $${LIBPATH}; then \
 				$(INSTALL) -D -m0755 $${LIBPATH} $(TARGET_DIR)/$${DESTDIR}/$${LIBNAME}; \