libgcrypt: use pkg-config to read gpg-error config data

Signed-off-by: Alejandro Mery <amery@geeks.cl>

security/libgcrypt/libgcrypt-gpg-error-pkgconfig.patch

@@ -0,0 +1,20 @@
+--- ./configure.ac~	2009-06-01 08:36:08.000000000 +0000
++++ ./configure.ac	2009-06-01 09:00:57.000000000 +0000
+@@ -511,11 +511,12 @@
+ #
+ # gpg-error is required.
+ #
+-AM_PATH_GPG_ERROR("$NEED_GPG_ERROR_VERSION")
+-if test "x$GPG_ERROR_LIBS" = "x"; then
+-  AC_MSG_ERROR([libgpg-error is needed.
+-                See ftp://ftp.gnupg.org/gcrypt/libgpg-error/ .])
+-fi
++PKG_CHECK_MODULES([GPG_ERROR], [gpg-error >= "$NEED_GPG_ERROR_VERSION"])
++#AM_PATH_GPG_ERROR("$NEED_GPG_ERROR_VERSION")
++#if test "x$GPG_ERROR_LIBS" = "x"; then
++#  AC_MSG_ERROR([libgpg-error is needed.
++#                See ftp://ftp.gnupg.org/gcrypt/libgpg-error/ .])
++#fi
+ 
+ AC_DEFINE(GPG_ERR_SOURCE_DEFAULT, GPG_ERR_SOURCE_GCRYPT,
+           [The default error source for libgcrypt.])

security/libgcrypt/libgcrypt.conf

@@ -12,6 +12,10 @@
 # GNU General Public License can be found in the file COPYING.
 # --- SDE-COPYRIGHT-NOTE-END ---
 
+# use system's gpg-error.m4
+hook_add preconf 3 'rm -f m4/gpg-error.m4'
+autogen=1
+
 if atstage cross; then
 	# gets wrongly detected
 	var_append configcache ' ' "ac_cv_sys_symbol_underscore=no"