move/remove macros from poppler-config.h that don't need to be there

popen/pclose are not used in any .h files - move to config.h

POPEN_READ_MODE is not used - remove
diff --git a/config.h.cmake b/config.h.cmake
index 4da6134..170963d 100644
--- a/config.h.cmake
+++ b/config.h.cmake
@@ -197,6 +197,14 @@
 #define snprintf _snprintf
 #endif
 
+//------------------------------------------------------------------------
+// popen
+//------------------------------------------------------------------------
+#if defined(_MSC_VER) || defined(__BORLANDC__)
+#define popen _popen
+#define pclose _pclose
+#endif
+
 /* Number of bits in a file offset, on hosts where this is settable. */
 #cmakedefine _FILE_OFFSET_BITS @_FILE_OFFSET_BITS@
 
diff --git a/poppler/poppler-config.h.cmake b/poppler/poppler-config.h.cmake
index ba6f5e3..4472e8f 100644
--- a/poppler/poppler-config.h.cmake
+++ b/poppler/poppler-config.h.cmake
@@ -134,21 +134,6 @@
 #define xpdfCopyright "Copyright 1996-2011 Glyph & Cog, LLC"
 
 //------------------------------------------------------------------------
-// popen
-//------------------------------------------------------------------------
-
-#if defined(_MSC_VER) || defined(__BORLANDC__)
-#define popen _popen
-#define pclose _pclose
-#endif
-
-#if defined(VMS) || defined(VMCMS) || defined(DOS) || defined(OS2) || defined(__EMX__) || defined(_WIN32) || defined(__DJGPP__) || defined(MACOS)
-#define POPEN_READ_MODE "rb"
-#else
-#define POPEN_READ_MODE "r"
-#endif
-
-//------------------------------------------------------------------------
 // Win32 stuff
 //------------------------------------------------------------------------