use autoconf macro to check for pkg-config (closes #15506)
diff --git a/Misc/NEWS b/Misc/NEWS
index c0c8603..af9274a 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -62,6 +62,9 @@
 Build
 -----
 
+- Issue #15506: Use standard PKG_PROG_PKG_CONFIG autoconf macro in the configure
+  script.
+
 - Issue #23032: Fix installer build failures on OS X 10.4 Tiger
   by disabling assembly code in the OpenSSL build.