Hi,

	A recent change to glibc removed asm/ptrace.h from user.h for AArch64. 
This meant that cross-native builds of gdb using trunk glibc broke 
because aarch64-linux-nat.c because user_hwdebug_state couldn't be found.

Fixed by including asm/ptrace.h like other ports.

Ok ?

regards
Ramana

2014-05-22  Ramana Radhakrishnan  <ramana.radhakrishnan@arm.com>

        * aarch64-linux-nat.c (asm/ptrace.h): Include.