misc: do not use "tar cf - |tar xf -"

Using this: tar cf - -C "/some/place" |tar xf - -C "/some/other/place"
to copy a directory to another place does not properly fail (when it does).

Using this instead: cp -av "/some/place" "/some/other/place"
makes it easy to see why and how it failed.

Impacted:
libc/uClibc
debug/ltrace
tools/sstrip
scripts/populate

 #!/bin/sh

 SKIP_ME="### CT_NG SKIP ME ###"

 skip_me=$(($(cat "${0}" |@@grep@@ --binary-files=text -o -b -E "^${SKIP_ME}$" |cut -d : -f 1)+${#SKIP_ME}+1))

 dd if="${0}" bs=${skip_me} skip=1 2>/dev/null |bzcat

 exit 0

 ### CT_NG SKIP ME ###