ALSA: ASoC: Don't suggest compile time selection of codec access

Currently the boiler plate code used by most ASoC codecs to provide a
placeholder for SPI access suggests making the selection of SPI a
compile time option which is suboptimal when trying to build kernels
supporting multiple systems.  Change this template to suggest allowing
runtime selection instead.

Leave the drivers not yet converted to new style I2C access for now to
avoid collisions.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@perex.cz>