Default to pkginstall=true without duplicated definitions

automake was complaining about duplicated definitions of pkginstall. It
was defined to true in Makefile.python.am only to be overriden in some
Makefile.am.

Now we assume that pkginstall is implicit true and only skip
installation when pkginstall is explicitly set to false.

Signed-off-by: Christian Heimes <cheimes@redhat.com>
Reviewed-By: Martin Basti <mbasti@redhat.com>

Makefile.python.am

@@ -1,6 +1,5 @@
 pkgname = $(shell basename "$(abs_srcdir)")
 pkgpythondir = $(pythondir)/$(pkgname)
-pkginstall = true
 
 if VERBOSE_MAKE
 VERBOSITY="--verbose"
@@ -20,7 +19,7 @@ all-local: $(top_builddir)/ipasetup.py
 		    --build-base "$(abs_builddir)/build"
 
 install-exec-local: $(top_builddir)/ipasetup.py
-	if [ "x$(pkginstall)" = "xtrue" ]; then \
+	if [ "x$(pkginstall)" != "xfalse" ]; then \
 	    $(PYTHON) $(srcdir)/setup.py \
 		    $(VERBOSITY) \
 		    build \