SharedForward: Hard-code the ldpath buffer size to below VS 14 limit

Visual Studio 14 (2015) complains if a static character array is
declared with more than 65535 elements.  This limit should be large
enough for SharedForward clients, so just hard-code that instead of
trying to compute a limit.

Change-Id: Ib24195b0d0972bdabaf5a18b93a1a9b8c43dc773

SharedForward.h.in

@@ -813,7 +813,7 @@ static void kwsys_shared_forward_print_failure(char const* const* argv)
 }
 
 /* Static storage space to store the updated environment variable.  */
-static char kwsys_shared_forward_ldpath[KWSYS_SHARED_FORWARD_MAXPATH*16] = KWSYS_SHARED_FORWARD_LDPATH "=";
+static char kwsys_shared_forward_ldpath[65535] = KWSYS_SHARED_FORWARD_LDPATH "=";
 
 /*--------------------------------------------------------------------------*/
 /* Main driver function to be called from main.  */