support for install

[Roland McGrath]

> > [...]
> > The answer was that the "make install" in my kernel only installs the
> > vmlinuz image in /boot, where systemtap needs the vmlinux one (no gzip
> > compression). Hope this will help someone else.
> 
> Good point.  I may have had to do that too, just forgot all about it.

We look for vmlinux in /boot/vmlinux-`uname -r` (or that subdir under
/usr/lib/debug).  This is not any kind of standard file name AFAIK, just
something I thought would be adequately convenient for people installing
hand-built kernels.  We also look for /lib/modules/`uname -r`/vmlinux
(really finding /usr/lib/debug/lib/...), which is where FC/RHEL kernel rpms
put the unstripped vmlinux.  We could provide an option to specify where to
look for the kernel binary.