ALSA: firewire-lib: code refactoring for parameters of packet queue and IRQ timing

Although the parameter for packet queue and IRQ timing is calculated when
AMDTP stream starts, the calculated parameters are the same between
streams in AMDTP domain.

This commit moves the calculation and decide the parameters when AMDTP
domain starts.

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Link: https://lore.kernel.org/r/20200508043635.349339-5-o-takashi@sakamocchi.jp


Signed-off-by: Takashi Iwai <tiwai@suse.de>