Drop support for poppler w/o cpp/poppler-version.h

Seems the first poppler including poppler-cpp.pc.in and also
cpp/poppler-version.h.in was 0.14.0.

So this also increases the minimal system poppler dependency from
* poppler 0.12.0 (Wed Sep 9, 2009)
to
* poppler 0.14.0 (Tue Jun 8, 2010)

Compiling the internal poppler, we're up-to-date anyway.

Change-Id: Iee07cfeb43f4320fd596c772eeb26662505d0daf
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/125778
Tested-by: Jenkins
Reviewed-by: Jan-Marek Glogowski <glogow@fbihome.de>

config_host/config_poppler.h.in

@@ -7,6 +7,4 @@ Settings for poppler header file detection
 
 #define ENABLE_PDFIMPORT 0
 
-#define HAVE_POPPLER_VERSION_H 0
-
 #endif

configure.ac

@@ -11992,27 +11992,14 @@ if test "$ENABLE_PDFIMPORT" = "TRUE" -a "$ENABLE_POPPLER" = "TRUE"; then
     if test "$with_system_poppler" = "yes"; then
         AC_MSG_RESULT([external])
         SYSTEM_POPPLER=TRUE
-        PKG_CHECK_MODULES( POPPLER, poppler >= 0.12.0 )
-        AC_LANG_PUSH([C++])
-        save_CXXFLAGS=$CXXFLAGS
-        save_CPPFLAGS=$CPPFLAGS
-        CXXFLAGS="$CXXFLAGS $POPPLER_CFLAGS"
-        CPPFLAGS="$CPPFLAGS $POPPLER_CFLAGS"
-        AC_CHECK_HEADER([cpp/poppler-version.h],
-            [AC_DEFINE([HAVE_POPPLER_VERSION_H], 1)],
-            [])
-        CXXFLAGS=$save_CXXFLAGS
-        CPPFLAGS=$save_CPPFLAGS
-        AC_LANG_POP([C++])
+        PKG_CHECK_MODULES(POPPLER,[poppler >= 0.14 poppler-cpp])
         POPPLER_CFLAGS=$(printf '%s' "$POPPLER_CFLAGS" | sed -e "s/-I/${ISYSTEM?}/g")
-
         FilterLibs "${POPPLER_LIBS}"
         POPPLER_LIBS="${filteredlibs}"
     else
         AC_MSG_RESULT([internal])
         SYSTEM_POPPLER=
         BUILD_TYPE="$BUILD_TYPE POPPLER"
-        AC_DEFINE([HAVE_POPPLER_VERSION_H], 1)
     fi
     AC_DEFINE([ENABLE_PDFIMPORT],1)
 fi

sdext/source/pdfimport/xpdfwrapper/pdfioutdev_gpl.hxx

@@ -55,14 +55,7 @@
 class GfxPath;
 class GfxFont;
 class PDFDoc;
-#if HAVE_POPPLER_VERSION_H
 #include <cpp/poppler-version.h>
-#else
-#define POPPLER_VERSION "0.12.3"
-#define POPPLER_VERSION_MAJOR 0
-#define POPPLER_VERSION_MINOR 12
-#define POPPLER_VERSION_MICRO 3
-#endif
 #define POPPLER_CHECK_VERSION(major,minor,micro) \
   (POPPLER_VERSION_MAJOR > (major) || \
    (POPPLER_VERSION_MAJOR == (major) && POPPLER_VERSION_MINOR > (minor)) || \