had_enable_audio_int() came from the LPE audio shell set_caps
callback with ENABLE_INT and DISABLE_INT caps.  I interpreted as these
correspond to enabling / disabling the audio interface, but the actual
implementation is only to clear (send ACK) to both BUFFER_DONE and
BUFFER_UNDERRUN interrupts unconditionally.  And, there is no
counterpart, DISABLE_INT, code at all.

For avoiding the further misunderstanding, rename the function to the
more fitting one, had_ack_irqs(), and drop the calls with enable=false
in allover places.  There is no functional changes at all.

After this patch, there is only one caller at the PCM trigger start.
Then it's doubtful whether this call is still really needed or not; I
bet it not, but let's stay in the safer side for now and keep it as
was.
Signed-off-by: Takashi Iwai <tiwai@suse.de>