[obvious/pushed] Fix "beneath" conversion on AIX

[Sergio Durigan Junior]

GDB build on AIX is broken according to BuildBot:

  ../../binutils-gdb/gdb/aix-thread.c: In member function 'virtual void aix_thread_target::mourn_inferior()':
  ../../binutils-gdb/gdb/aix-thread.c:1735:34: error: 'beneath' cannot be used as a function
     target_ops *beneath = beneath ();
				    ^
This obvious commit fixes it.  There's apparently another issue
breaking the build there, but that's unrelated.

gdb/ChangeLog:
2018-06-14  Sergio Durigan Junior  <sergiodj@redhat.com>

	* aix-thread.c (aix_thread_target::xfer_partial): Use
	"beneath" as a method.
---
 gdb/aix-thread.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/gdb/aix-thread.c b/gdb/aix-thread.c
index 8b1b0ed97f..643d3213f0 100644
--- a/gdb/aix-thread.c
+++ b/gdb/aix-thread.c
@@ -1732,7 +1732,7 @@ aix_thread_target::xfer_partial (enum target_object object,
 void
 aix_thread_target::mourn_inferior ()
 {
-  target_ops *beneath = beneath ();
+  target_ops *beneath = this->beneath ();
 
   pd_deactivate ();
   beneath->mourn_inferior ();
-- 
2.14.3