Move have_ptrace_getregset to linux-nat.c

I'll let arm-linux-nat.c to use PTRACE_GETREGSET if kernel supports,
so this patch is to move have_ptrace_getregset from x86-linux-nat.c
to linux-nat.c.

gdb:

2015-06-01  Yao Qi  <yao.qi@linaro.org>

	* x86-linux-nat.c (have_ptrace_getregset): Move it to ...
	* linux-nat.c: ... here.
	* x86-linux-nat.h (have_ptrace_getregset): Move the declaration
	to ...
	* linux-nat.h: ... here.

1 files changed, 3 insertions, 0 deletions

diff --git a/gdb/linux-nat.c b/gdb/linux-nat.c
index f95e76c601..febee84bdd 100644
--- a/gdb/linux-nat.c
+++ b/gdb/linux-nat.c
@@ -163,6 +163,9 @@ blocked.  */
 #define O_LARGEFILE 0
 #endif
 
+/* Does the current host support PTRACE_GETREGSET?  */
+int have_ptrace_getregset = -1;
+
 /* The single-threaded native GNU/Linux target_ops.  We save a pointer for
    the use of the multi-threaded target.  */
 static struct target_ops *linux_ops;