Merged revisions 320573 via svnmerge from

https://origsvn.digium.com/svn/asterisk/branches/1.8

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  r320573 | tilghman | 2011-05-23 11:19:32 -0500 (Mon, 23 May 2011) | 7 lines
  
  GNU libiconv uses symbol "libiconv_open" instead of "iconv_open".
  
  (closes issue #19344)
   Reported by: rohanl
   Patches: 
         iconv-check.patch uploaded by rohanl (license 1284)
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git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@320579 65c4cc65-6c06-0410-ace0-fbb531ad65f3

configure.ac

@@ -1142,6 +1142,8 @@ if test "${USE_GSM}" != "no"; then
 fi
 
 AST_EXT_LIB_CHECK([ICONV], [iconv], [iconv_open], [iconv.h])
+# GNU libiconv #define's iconv_open to libiconv_open, so we need to search for that symbol
+AST_EXT_LIB_CHECK([ICONV], [iconv], [libiconv_open], [iconv.h])
 # Some versions of Linux package iconv in glibc
 AST_EXT_LIB_CHECK([ICONV], [c], [iconv_close], [iconv.h])