LBR, BTM, or BTS records may have incorrect branch "from" information afer an

LBR, BTM, or BTS records may have incorrect branch "from" information afer an
EIST transition, T-states, C1E, or Adaptive Thermal Throttling (AAJ122).

This results in sporadic test fails. Disable btrace on those processors.

gdb/
	* common/linux-btrace.c: Include sys/ptrace, sys/types, sys/wait.h,
	and signal.h.
	(linux_supports_btrace): Add kernel and
	cpuid check.
	(kernel_supports_btrace): New function.
	(cpu_supports_btrace): New function.
	(intel_supports_btrace): New function.