Add some quotes in the makefile snippet that creates the temporary
installation, so that it can handle spaces in the directory name and
possibly some other oddities.
define prove_check
$(MKDIR_P) tmp_check/log
-$(MAKE) -C $(top_builddir) DESTDIR=$(CURDIR)/tmp_check/install install >$(CURDIR)/tmp_check/log/install.log 2>&1
+$(MAKE) -C $(top_builddir) DESTDIR='$(CURDIR)'/tmp_check/install install >'$(CURDIR)'/tmp_check/log/install.log 2>&1
cd $(srcdir) && TESTDIR='$(CURDIR)' PATH="$(CURDIR)/tmp_check/install$(bindir):$$PATH" $(call add_to_path,$(ld_library_path_var),$(CURDIR)/tmp_check/install$(libdir)) PGPORT='6$(DEF_PGPORT)' $(PROVE) $(PG_PROVE_FLAGS) $(PROVE_FLAGS) t/
endef