Fix sqlite3 plugin detection

(cherry picked from commit c413f6060b)

acinclude.m4.in

@@ -1252,7 +1252,7 @@ AC_DEFUN([KDE_USE_QT],
     AC_MSG_RESULT(Detected TQt3...)
   fi
   if test "$kde_qtver" = "4"; then
-    AC_MSG_RESULT(Detected TQt4...)
+    AC_MSG_RESULT(Detected Qt4...)
   fi
 
 #else
@@ -6721,7 +6721,19 @@ AC_DEFUN([AC_SQLITE3], [
       QTDIR=`dirname $MOC`
       QTDIR=${QTDIR%/bin}
     fi
-    LIBSQLITE3=${QTDIR}/plugins/sqldrivers/libsqlite3${qtlib}.so
+    if test "$PKG_CONFIG" != "no" ; then
+      if $PKG_CONFIG --exists qt-mt ; then
+        qt_plugins_dir="`pkg-config --variable=pluginsdir qt-mt`"
+      else
+        if $PKG_CONFIG --exists tqt-mt ; then
+          qt_plugins_dir="`pkg-config --variable=pluginsdir tqt-mt`"
+        fi
+      fi
+    fi
+    if test "x$qt_plugins_dir" = "x"; then
+      qt_plugins_dir=${QTDIR}/plugins
+    fi
+    LIBSQLITE3=${qt_plugins_dir}/sqldrivers/libqsqlite3${qtlib}.so
 
     # do the checks
     if test $enable_sqlite3 = auto; then