Patch Upstream: x86 ptrace: fix PTRACE_GETFPXREGS error

Patch Upstream: x86 ptrace: fix PTRACE_GETFPXREGS error

commit 45fdc3a7624a4a48185a04ae0abab5f9793d8952 upstream

ptrace has always returned only -EIO for all failures to access
registers.  The user_regset calls are allowed to return a more
meaningful variety of errors.  The REGSET_XFP calls use -ENODEV
for !cpu_has_fxsr hardware.  Make ptrace return the traditional
-EIO instead of the error code from the user_regset call.

Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>