ASoC: allow drivers to compile both static and dynamic

Based on where the code is synced the driver should allow
both static and dynamic linked compilation.
Also remove __exit for modules loaded from another common
init/exit functions.

Change-Id: Ib58f152002aba3af4446f9bbd9b82c279212bd0a
Signed-off-by: Asish Bhattacharya <asishb@codeaurora.org>
diff --git a/dsp/rtac.c b/dsp/rtac.c
index 806bbc5..43c69cc 100644
--- a/dsp/rtac.c
+++ b/dsp/rtac.c
@@ -1949,7 +1949,7 @@
 	return -ENOMEM;
 }
 
-void __exit rtac_exit(void)
+void rtac_exit(void)
 {
 	kzfree(rtac_adm_buffer);
 	kzfree(rtac_asm_buffer);