ALSA: hdac: Explicitly add io.h

Compiling the hdac extended core on arm fails with below error:

  sound/hda/ext/hdac_ext_bus.c: In function 'hdac_ext_writel':
>> sound/hda/ext/hdac_ext_bus.c:29:2: error: implicit declaration of
>> function
+'writel' [-Werror=implicit-function-declaration]
     writel(value, addr);
     ^
   sound/hda/ext/hdac_ext_bus.c: In function 'hdac_ext_readl':
>> sound/hda/ext/hdac_ext_bus.c:34:2: error: implicit declaration of
>> function
+'readl' [-Werror=implicit-function-declaration]
     return readl(addr);

This is fixed by explicitly including io.h

Fixes: 99463b3a3994 - ('ALSA: hda: provide default bus io ops extended hdac')
Reported-by: kbuild test robot <[email protected]>
Suggested-by: Mark Brown <[email protected]>
Signed-off-by: Vinod Koul <[email protected]>
Signed-off-by: Takashi Iwai <[email protected]>

0 files changed, 0 insertions, 0 deletions