Re: dtc: Improve the make install target

So, like, the other day David Gibson mumbled:

This patch makes various improvements to dtc's make install target:
	- libfdt is also installed.  Specifically, libfdt.a and the
two export relevant header files, fdt.h and libfdt.h are installed.
	- ftdump is no longer installed.  It was only ever a
development debugging tool and may well go away at some point.
	- In keeping with normal conventions, there is now a PREFIX
variable, allowing control of where things are installed (in /usr,
/usr/local, /opt, etc.).
	- By default, installed into the user's home directory,
instead of /usr.  This is friendlier for self-installers, package
builders can easily override PREFIX to restore the old behaviour.

Signed-off-by: David Gibson <redacted>

Applied.

Thanks,
jdl