Fix up "make check"

While running make check, I noticed that it was actually using
the virsh binary from my system, in /usr/bin/virsh, and not the
one that was just compiled.  This is actually caused by a bug
in Makefile.am, where we didn't update the PATH to include tools.

While here, I also updated all of the scripts to properly define
the srcdir, abs_top_srcdir, and abs_top_builddir environment
variables.  This is required if you want to be able to run the
tests standalone (i.e. ./test instead of from make check).  I've
tested this on both RHEL-5 and Fedora-10 machines, and make check
works on both, as does running the individual tests by hand.

Signed-off-by: Chris Lalancette <clalance@redhat.com>

tests/define-dev-segfault

@@ -2,13 +2,15 @@
 # Exercise a bug whereby defining a valid domain could kill libvirtd.
 # The bug can also be exercised with a simple define/dumpxml pair to virsh.
 
-if test "$VERBOSE" = yes; then
-  set -x
-  virsh --version
-fi
-
 test -z "$srcdir" && srcdir=$(pwd)
 test -z "$abs_top_srcdir" && abs_top_srcdir=$(pwd)/..
+test -z "$abs_top_builddir" && abs_top_builddir=$(pwd)/..
+
+if test "$VERBOSE" = yes; then
+  set -x
+  $abs_top_builddir/tools/virsh --version
+fi
+
 . "$srcdir/test-lib.sh"
 
 fail=0
@@ -62,7 +64,7 @@ cat <<\EOF > D.xml || fail=1
 EOF
 
 url=test:///default
-virsh --connect "$url" 'define D.xml; dumpxml D' > out 2>&1 || fail=1
+$abs_top_builddir/tools/virsh --connect "$url" 'define D.xml; dumpxml D' > out 2>&1 || fail=1
 
 cat > exp <<EOF || fail=1
 Domain D defined from D.xml