configure.ac: explicitly require pkg-config related macro

Make sure the PKG_PROG_PKG_CONFIG macro has become available before it
gets used. This unbreaks configuration in the poky environment (rocko).

diff --git a/configure.ac b/configure.ac
index 80536f8faad4671ce7772624cfe5549f4975dd6d..d03f9831b25eb48b4ad89edea00b81ea9fedb924 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -67,6 +67,10 @@ SR_LIB_VERSION_SET([SRD_LIB_VERSION], [4:0:0])
 
 AM_CONDITIONAL([WIN32], [test -z "${host_os##mingw*}" || test -z "${host_os##cygwin*}"])
 
+# Initialize pkg-config.
+# We require at least 0.22, as "Requires.private" behaviour changed there.
+PKG_PROG_PKG_CONFIG
+
 ############################
 ##  Package dependencies  ##
 ############################