So that building from an archive works even if intltool is not present.
The README file already mentioned that intltool should only be required
when building from git.
Tested: Built it from the distribution archive on a host without intltool.
$ ./configure --enable-polkit
$ make
$(AM_V_M4)$(M4) -P $(M4_DEFINES) -DFOR_USER=1 < $< > $@
if ENABLE_POLKIT
-nodist_polkitpolicy_DATA = \
+dist_polkitpolicy_DATA = \
$(polkitpolicy_files) \
$(polkitpolicy_in_in_files:.policy.in.in=.policy)
endif