ASoC: wcd937x: Fix invalid memory access in wcd937x_suspend

Invalid memory access happens in wcd937x_suspend if
component bind for slave fails. This is because
as part of component_unbind devres_release_group is called
which removes every node from list and frees corresponding memory.
This results in invalid memory access for wcd937x in wcd937x_suspend.
Do kfree and set drvdata to NULL if component_bind fails
to resolve the issue.

Change-Id: Ia26eb36fe8b92ac0491b03d0d4a2b8def415148b
Signed-off-by: Vatsal Bucha <vbucha@codeaurora.org>