acerhdf: Adding support for new models

added following new models:
   * Aspire 5755G
   * AO521
   * AO751h
   * Aspire One 753
   * Extensa 5420
   * Aspire 5315
   * Aspire 5739G
   * TravelMate TM8573T

Cc: platform-driver-x86@vger.kernel.org
Cc: Darren Hart <dvhart@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andreas Mohr <andi@lisas.de>
Acked-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Peter Feuerer <peter@piie.net>
Signed-off-by: Darren Hart <dvhart@linux.intel.com>