[PATCH] Fix compiler warnings building against Linux uapi headers

[Yao Qi]

enh <enh@google.com> writes:

> 2015-08-25  Elliott Hughes  <enh@google.com>
>
>         * arm-linux-tdep.h, linux-arm-low.c: Only define HWCAP_VFP and
>         friends if they're not already defined. Fixes build against Linux
>         uapi headers.

We need two changelog entries for gdb/ChangeLog and
gdb/gdbserver/ChangeLog respectively.  The last sentence "Fixes build
against Linux uapi headers" is not needed.

OK with the changes.

-- 
Yao (齐尧)