perf unwind: Fix libunwind build failure on i386 systems

perf unwind: Fix libunwind build failure on i386 systems

Naresh Kamboju reported, that on the i386 build pr_err()
doesn't get defined properly due to header ordering:

  perf-in.o: In function `libunwind__x86_reg_id':
  tools/perf/util/libunwind/../../arch/x86/util/unwind-libunwind.c:109:
  undefined reference to `pr_err'

Reported-by: Naresh Kamboju <[email protected]>
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
Cc: David Ahern <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: [email protected]
Signed-off-by: Ingo Molnar <[email protected]>