kernel-module-split.bbclass: Allow autoloading multiple modules or modules where...

kernel-module-split.bbclass: Allow autoloading multiple modules or modules where basename != module name

* new KERNEL_MODULE_AUTOLOAD syntax doesn't support modules where basename and
  module name don't match (usually - and _), e.g.:

  module_autoload_bq27x00_battery = "bq27x00-battery"

* sometimes it's useful to load modules in particular order and
  module_autoload allowed to just list multiple modules, e.g.:

  module_autoload_snd-soc-neo1973-wm8753 = "snd-soc-s3c24xx snd_soc_s3c24xx_i2s snd-soc-dfbmcs320 snd-soc-wm8753 snd-soc-neo1973-wm8753"
  or
  module_autoload_g_ether = "s3c2410_udc g_ether"

  restore this possibility which is useful for incorrect dependencies
  between modules

Signed-off-by: Martin Jansa <Martin.Jansa@gmail.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>