ALSA: timer: Follow standard EXPORT_SYMBOL() declarations

[ Upstream commit 988563929d5b65c021439880ac6bd1b207722f26 ]

Just a tidy up to follow the standard EXPORT_SYMBOL*() declarations
in order to improve grep-ability.

- Move EXPORT_SYMBOL*() to the position right after its definition

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>