ASoC: msm: Fix sound card registration failure

In external codec machine driver, register
SSR notifier after sound card register. Also,
add separate snd_soc_card variables for tavil
and tasha since same machine driver is used
for both codecs.

CRs-Fixed: 1083537
Change-Id: I73fc02b812f2e6694e2a6aa8bdad2381a5f19406
Signed-off-by: Laxminath Kasam <lkasam@codeaurora.org>