[Bug 21503] New: WINEDEBUG=+heap shows valgrind warnings in virtual_init()

http://bugs.winehq.org/show_bug.cgi?id=21503

Summary: WINEDEBUG=+heap shows valgrind warnings in
                    virtual_init()
           Product: Wine
           Version: 1.1.37
          Platform: x86
        OS/Version: Linux
            Status: NEW
          Keywords: patch, source
          Severity: normal
          Priority: P2
         Component: ntdll
        AssignedTo: [e-mail]
        ReportedBy: [e-mail]

This is after Alexandre's heap commits today.
It's the next bug after 21502.

Running any test under valgrind with +heap, e.g.
WINEDEBUG=+heap WINETEST_WRAPPER=valgrind make atom.ok 
shows a warning in virtual_init():

preloader: Warning: failed to reserve range 00110000-68000000
Warning: set address range perms: large range [0x82000000, 0xbeb80000)
(defined) 
Invalid read of size 4 
   at HEAP_ValidateFreeArena (heap.c:1130)
   by HEAP_IsRealArena (heap.c:1313)
   by HEAP_GetPtr (heap.c:433)
   by RtlAllocateHeap (heap.c:1534)
   by create_view (virtual.c:467)
   by virtual_init (virtual.c:1356)
   by thread_init (thread.c:203)
   by __wine_process_init (loader.c:2850)
   by wine_init (loader.c:711)
   by main (main.c:218)
 Address 0xbfc00138 is not stack'd, malloc'd or (recently) free'd

Line 1130 of heap.c is
            if (*ptr != ARENA_FREE_FILLER)

This is due to missing valgrind annotations in HEAP_ValidateFreeArena();
it has to grant itself access temporarily.
Draft patch attached that fixes the problem.