Macro AST_PKG_CONFIG_CHECK to use chkconfig

AST_PKG_CONFIG_CHECK: Similar to AST_EXT_LIB_CHECK, but simply uses
pkg-config data.

This simple version only uses pkg-config(1)'s tests.

This commit also uses the macro to test for GTK2 and GMIME (instead of
the current direct usage of pkg-config).

Review: https://reviewboard.asterisk.org/r/1906/



git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@366351 65c4cc65-6c06-0410-ace0-fbb531ad65f3

autoconf/ast_pkgconfig.m4

@@ -0,0 +1,17 @@
+# Check for pkg-config component $2:
+# AST_PKG_CONFIG_CHECK([package], [component])
+AC_DEFUN([AST_PKG_CONFIG_CHECK],
+[
+   if test "x${PBX_$1}" != "x1" -a "${USE_$1}" != "no"; then
+      PKG_CHECK_MODULES($1, $2, [
+            PBX_$1=1
+            $1_INCLUDE="$$1_CFLAGS"
+            $1_LIB="$$1_LIBS"
+            AC_DEFINE([HAVE_$1], 1, [Define if your system has the $1 libraries.])
+         ], [
+            PBX_$1=0
+         ]
+      )
+   fi
+])
+