build system: correct warning about subdir-objects

This suppresses this category of warnings when running build.sh:

src/Makefile.am:NNN: warning: source file 'XXX' is in a subdirectory,
src/Makefile.am:NNN: but option 'subdir-objects' is disabled

diff --git a/src/Makefile.am b/src/Makefile.am
index b8a272a..6c7a1d4 100644 (file)
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -17,6 +17,8 @@ endif
 AM_CPPFLAGS += -DPLUGINDIR='"${pkglibdir}"'
 AM_CPPFLAGS += -DPKGDATADIR='"${pkgdatadir}"'
 
+AUTOMAKE_OPTIONS = subdir-objects
+
 sbin_PROGRAMS = collectd collectdmon
 bin_PROGRAMS = collectd-nagios collectdctl collectd-tg