Correct typed_flags<PivotFunc> mask is 0x1fff

This was wrong since

    commit 298ee506
    CommitDate: Sun Nov 20 00:14:28 2016 +0100

        PivotMedian: Implement median as a new pivot table function

and in fact in a debug build failed an assertion

soffice.bin: include/o3tl/typed_flags_set.hxx:85:
  constexpr o3tl::is_typed_flags<E, M>::Wrap::Wrap(type name std::underlying_type<_Tp>::type)
  [with E = PivotFunc; typename std::underlying_type<_Tp>::type M = 4607; typename std::underlying_type<_Tp>::type = int]:
  Assertion `static_cast<typename std::underlying_type<E>::type>(~0) == M || (value & ~M) == 0' failed.

when one of the functions (e.g. StdVar) not included in the mask
was chosen as pivot table data function.

Change-Id: I5b9efc7d2cbcf6fece3ef228db8f6e0ffa17b510
Reviewed-on: https://gerrit.libreoffice.org/64974Reviewed-by: Eike Rathke <erack@redhat.com>
Tested-by: Jenkins

sc/inc/dpglobal.hxx

@@ -39,7 +39,7 @@ enum class PivotFunc {
     Auto         = 0x1000
 };
 namespace o3tl {
-    template<> struct typed_flags<PivotFunc> : is_typed_flags<PivotFunc, 0x11ff> {};
+    template<> struct typed_flags<PivotFunc> : is_typed_flags<PivotFunc, 0x1fff> {};
 }
 
 struct ScDPValue