Makefile: Move some scripts imported from Linux

We have some scripts imported from Linux Kernel:
setlocalversion, checkstack.pl, checkpatch.pl, cleanpatch

They are located under tools/ directory in U-Boot now.
But they were originally located under scripts/ directory
in Linux Kernel.

This commit moves them to the original location.

It is true that binutils-version.sh and dtc-version.sh
do not originate in Linux Kernel, but they should
be moved by analogy to gcc-version.sh.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>