Fix dlfcn/failtestmod.c warning

[Ondřej Bílka]

On Wed, Nov 26, 2014 at 09:11:19PM +0000, Joseph Myers wrote:
> This patch fixes a "set but not used" warning from
> dlfcn/failtestmod.c.  A variable is used only to store the return
> value from dlsym.  As I understand this test, the point is simply to
> do a sequence of load / unload operations in a loop, and all that
> matters here is that dlsym gets called and returns without crashing,
> not what its return value is.  So this patch removes the assignment to
> a variable.
> 
> Tested for x86_64.
> 
looks ok.