platform/x86: acerhdf: Remove cut-and-paste trap from instructions

Just like we avoid specifying actual block devices like sda for fdisk
and dd examples, we should not specify specific thermal zones here.

On the platform I was testing on, zone0 was acpitz, and zone1 was for
this acerhdf driver.  Make the printk such that it won't work with a
blind cut-and-paste, and force the user to determine which zone is
correct for this driver.

Cc: Peter Feuerer <peter@piie.net>
Cc: Darren Hart <dvhart@infradead.org>
Cc: Andy Shevchenko <andy@infradead.org>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Peter Feuerer <peter@piie.net>