ASoC: Intel: avs: Fix build error on arc, m68k and sparc

ASoC: Intel: avs: Fix build error on arc, m68k and sparc

On some platforms (i.e. arc, m68k and sparc) __fls returns an int (while
on most platforms it returns an unsigned long). This triggers a format
warning on these few platforms as the driver uses %ld to print a warning.

So explicitly cast the return value to unsigned long to make the warning
go away (and so fix allmodconfig build on the affected architectures).

Fixes: 0dc3a5e87ec0 ("ASoC: Intel: avs: Machine board registration")
Reviewed-by: Cezary Rojewski <cezary.rojewski@intel.com>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20220529141250.1979827-1-u.kleine-koenig@pengutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>