Add coverity target to corosync makefile.am

Allow a make coverity target for those developers with coverity tools
available to them.

Signed-off-by: Steven Dake <sdake@redhat.com>
Reviewed-by: Angus Salkeld <asalkeld@redhat.com>

Makefile.am

@@ -67,6 +67,11 @@ endif
 SUBDIRS			= include lcr lib exec services tools test cts pkgconfig \
 			  man init conf
 
+coverity:
+	cov-build --dir=cov make
+	cov-analyze --dir cov
+	cov-format-errors --dir cov
+
 install-exec-local:
 	$(INSTALL) -d $(DESTDIR)/${COROSYSCONFDIR}/service.d
 	$(INSTALL) -d $(DESTDIR)/${COROSYSCONFDIR}/uidgid.d