Add pkgconfig support to libassuan.
This patch is rejected by upstream for the reason below:
They think pkgconfig adds no portability and maintaining them is not worthwhile.

Upstream-Status: Rejected
Signed-off-by: Chen Qi <Qi.Chen@windriver.com>
Signed-off-by: Constantin Musca <constantinx.musca@intel.com>

Index: libassuan-2.1.0/Makefile.am
===================================================================
--- libassuan-2.1.0.orig/Makefile.am
+++ libassuan-2.1.0/Makefile.am
@@ -24,10 +24,13 @@ AUTOMAKE_OPTIONS = dist-bzip2 no-dist-gz
 # (A suitable gitlog-to-changelog script can be found in GnuPG master.)
 GITLOG_TO_CHANGELOG=gitlog-to-changelog
 
+pkgconfigdir = $(libdir)/pkgconfig
+pkgconfig_DATA = assuan.pc
+
 EXTRA_DIST = config.rpath autogen.sh README.GIT                  	\
              ChangeLog-2011 doc/ChangeLog-2011 src/ChangeLog-2011 	\
              tests/ChangeLog-2011 contrib/ChangeLog-2011     		\
-             build-aux/git-log-footer build-aux/git-log-fix
+             build-aux/git-log-footer build-aux/git-log-fix assuan.pc.in
 
 SUBDIRS = m4 src doc tests
 
Index: libassuan-2.1.0/assuan.pc.in
===================================================================
--- /dev/null
+++ libassuan-2.1.0/assuan.pc.in
@@ -0,0 +1,12 @@
+prefix=@prefix@
+exec_prefix=@exec_prefix@
+libdir=@libdir@
+includedir=@includedir@
+
+Name: libassuan
+Description: IPC library used by GnuPG and GPGME
+Requires:
+Version: @VERSION@
+Libs: -L${libdir} -lassuan
+Libs.private: -lgpg-error
+Cflags: -I${includedir}
Index: libassuan-2.1.0/configure.ac
===================================================================
--- libassuan-2.1.0.orig/configure.ac
+++ libassuan-2.1.0/configure.ac
@@ -433,7 +433,7 @@ AC_CONFIG_FILES([doc/Makefile])
 AC_CONFIG_FILES([tests/Makefile])
 AC_CONFIG_FILES([src/libassuan-config], [chmod +x src/libassuan-config])
 AC_CONFIG_FILES([src/versioninfo.rc])
-
+AC_CONFIG_FILES([assuan.pc])
 AC_OUTPUT
 
 echo "