internal: don't use weak symbols for Win32 platform

The Win32 platform will fail to link if you use weak symbols
because it is incompatible with exporting symbols in a DLL:

Cannot export virRandomGenerateWWN: symbol wrong type (2 vs 3)

We only need weak symbols for our test suite to do LD_PRELOAD
and this doesn't work on Win32, so we can just drop the hack
for Win32
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

src/internal.h

@@ -128,12 +128,16 @@
  *
  */
 # ifndef ATTRIBUTE_MOCKABLE
+#  if defined(WIN32)
+#   define ATTRIBUTE_MOCKABLE
+#  else
 #   if __GNUC_PREREQ(4, 5)
 #    define ATTRIBUTE_MOCKABLE __attribute__((__noinline__, __noclone__, __weak__))
 #   else
 #    define ATTRIBUTE_MOCKABLE __attribute__((__noinline__, __weak__))
 #   endif
 #  endif
+# endif
 
 /**
  * ATTRIBUTE_FMT_PRINTF